An air bag jack raises a load by inflating a reinforced bag or bladder with compressed shop air. There is no pump handle and no ram to stroke: you open a valve, the bag fills, and the load comes up. The RakJak and ESCO Pro Series listings both sell that speed, "speed and portability" on the GOJ-TBT2 and "a safe and fast solution" on the 92040 and 92041, which is why air jacks live on frame racks, alignment racks and tire benches, and it is also why they show up in heavy-duty work where a flat inflatable jack has to slide into a gap a bottle jack cannot enter.
This category holds 25 items across four brands: ESCO (17 items), Herkules (5), RakJak, built by Zendex Tool Corp. (2), and iDEAL (1). Nine are complete jacks ready to connect, five are bare ESCO air bags that need a valve, hose and nipple to go into service, four are pre-packaged ESCO air bag kits, and seven are extensions, valves, hoses and adapters. Everything here is new equipment. Published capacities run from 2 tons up to 70 tons, maximum heights go up to 22 in., and clearance to get started ranges from 4.5 in. on the lowest rolling jack down to the one inch the flat ESCO bags need. Below is what actually separates one air jack from another, using only the figures printed on these product pages.
▸ Read the full Air Bag Jacks buying guide — types, capacity, power and space, comparison table and FAQs
Three Different Machines Share the Name "Air Jack"
Buyers searching for an air jack, an airbag jack or an inflatable jack are usually looking at one of three very different tools. Picking the wrong family is the most common and most expensive mistake in this category.
1. Bag-and-frame air jacks (double bag and triple bag)
These are portable units with a handle carrying the air controls and two or three stacked bags. You position one under a lift point, press the up control, and the stacked bags telescope. The Herkules AJ-2 (double bag) and AJ-3 (triple bag) and the RakJak GOJ-TBT2 and GOJ-TBT3 (both triple bag) belong here. Both Herkules units are described as 100 percent air operated, needing 90 to 110 psi of standard shop air, and both are rated at 4,500 lb. Both RakJak listings specify a portable handle type; nothing in this category is a rolling floor jack. The GOJ-TBT2 listing describes it as widely used on frame and alignment racks, with speed and portability making it suited to tire, wheel and suspension work. The GOJ-TBT3 listing positions the 3 ton version for high-clearance and heavy-duty lifting in automotive repair, body shops and alignment centers, and states it is manufactured in the USA by Zendex Tool Corp.
The practical difference between a double bag and a triple bag is not capacity, it is reach. The Herkules AJ-2 and AJ-3 carry the same 4,500 lb rating, but the double-bag AJ-2 starts at 6.5 in. and the triple-bag AJ-3 starts at 7.875 in. and goes up to 19.25 in. A third bag buys you height and costs you a lower collapsed profile.
2. Bladder jacks and the ESCO Pro Series stacked-bag jacks
A bladder jack uses a single high-resistance diaphragm with an internal telescoping guide instead of stacked bags. The ESCO YAK line (92011, 92013) is built around a highly resistant diaphragm with an internal telescope guide. The YAK listings note a limit stop device plus a safety valve for excessive loads, and describe them as silent, simple and lightweight, suited to tire technicians and bodywork shops, with the specific note that they can also be used on column lifts. The iDEAL FR-BagJack, rated 4,400 lbs, is a 2-stage air bladder jack with an internal telescoping stabilization sleeve, a multi-position handle and an over-inflation pressure relief valve, and is listed as a companion for the FR-77 18-foot tilt deck and similar frame racks. The ESCO Pro Series is a different build: the 92040 is named a double bag and the 92041 a triple bag, and their pages describe heavy duty air-bags, a large bottom plate for added stability, and a dual safety valve that prevents both over-inflation and uncontrolled descent of the jack under load.
3. Flat inflatable air bags (ESCO Maximum Force)
These are not rolling jacks at all. ESCO Maximum Force air bags are thin, molded, five-layer aramid fiber pads that measure 1 in. thick deflated and can be positioned in as little as one inch of clearance. The listings name material handling, railroad work, mining, rescue, military, agricultural and OTR tire changing as their applications. Five capacities are listed: 13 ton (12105), 22 ton (12107), 32 ton (12109), 50 ton (12112) and 70 ton (12113). Only the 70 ton 12113 and its 12113K kit can be ordered from the site right now; the 13, 22, 32 and 50 ton bags and the 12107K, 12109K and 12112K kits are marked "Call us up for availability!", so call 800-562-4791 to confirm before you plan a job around one. These are the products behind the very large tonnage figures in this category, and they are a completely different purchase from a shop air jack.
Capacity: 2 to 3 Tons for Cars, 13 to 70 Tons for Flat Bags
The rolling-jack group tops out at the 3 ton (6,000 lb) RakJak GOJ-TBT3. Everything else sits at or below 4,500 lb: the Herkules AJ-2 and AJ-3 are 4,500 lb, the iDEAL FR-BagJack is 4,400 lbs, the ESCO Pro Series 92040 and 92041 are 2 tons (4,000 lb), the ESCO YAK 92011 and 92013 are 2.2 ton, and the RakJak GOJ-TBT2 is 2 ton at 105 psi. That range covers the vehicles these listings name: the iDEAL FR-BagJack is listed to lift "most passenger vehicles and light trucks", and the ESCO Pro Series pages target "automotive, SUV and Light Truck applications", including use as an additional support on a frame machine to lift in small increments. Match the jack to the weight actually on the lift point, and follow the model's own manual.
If you need 13 tons or more, you are buying a flat ESCO bag, and the trade-off is height. Inside the flat bag range, capacity and lift height climb together: 13 ton reaches 7.5 in., 22 ton 9.5 in., 32 ton 12 in., 50 ton 15 in. and 70 ton 18 in. What no flat bag matches is the travel of a bladder jack: the 2 ton ESCO 92041 reaches 22 in., higher than the 70 ton 12113. Decide the gap you need to close before you decide the tonnage.
Collapsed Height and Maximum Height
Collapsed height decides whether the jack fits under the vehicle at all. In this category the lowest published minimum on a rolling jack is 4.5 in. on the ESCO 92040, followed by 5.2 in. on the ESCO YAK 92011 and 5 5/16 in. on the iDEAL FR-BagJack. The tallest published maximum is 22 in. on the ESCO 92041, which reaches that figure only by combining its stages plus the included 2.25 in. (60 mm) extension. Next are the ESCO YAK 92013 at 19.29 in. and the Herkules AJ-3 at 19.25 in.
Both ESCO Pro Series jacks ship with an extension already in the box, 3 in. (80 mm) on the 92040 and 2.25 in. (60 mm) on the 92041, so you do not need to buy height separately on those two. The 92040 table publishes a 4.5 in. minimum height and a 9.25 in. extended height but no combined maximum, so its usable maximum is above the 9.25 in. printed in the table; consult the 92040 spec sheet for the total.
Herkules also sells height separately in this category: the AJ-X50 is a 2 in. extension and the AJ-X100 is a 4 in. extension, both listed for the AJ2 or AJ3, with the cap sold separately on each. The ESCO 92017 is a 2.68 in. extension rated 2.2 ton for the YAK 92011 and 92013. The Herkules 10454 pinch weld adapter is listed for the AJ2 or AJ3 and is the part you want if you are lifting unibody cars on their seams.
What You Need in the Shop
The requirement these units share is air, not electricity: no listing in this category publishes a voltage, a phase or a motor rating, because there is no motor. What each family does publish is a working pressure, and the spread matters if your compressor runs on the low side.
- Herkules AJ-2 and AJ-3: 90 to 110 psi standard shop air.
- iDEAL FR-BagJack: 100 psi.
- RakJak GOJ-TBT2: rated 2 ton at 105 psi.
- ESCO Pro Series 92040 and 92041: 100 to 145 psi working air pressure.
- ESCO YAK 92011 and 92013: 116 to 145 psi working air pressure.
A shop regulated at 90 psi will run the Herkules units at their rated pressure but sits below the published working range of both ESCO YAK jacks. The RakJak GOJ-TBT3 and the ESCO Maximum Force flat bags do not publish a working pressure on their listings; consult the spec sheet on those model pages before you size a supply.
Floor and ceiling are not a factor the way they are with a two post lift, since nothing here is anchored, but weight and footprint are. The RakJak GOJ-TBT2 weighs 44.5 lbs in a 11.25 x 19.75 x 8.25 in. package and the GOJ-TBT3 weighs 61.75 lbs at 13.5 x 22 x 8.625 in. with a 12 in. air bag; the Herkules AJ-2 is 33 lbs and the AJ-3 is 37 lbs; the ESCO YAK jacks are 31 and 37 lbs with a 16.34 in. overall width and a 9.84 in. bladder; the iDEAL FR-BagJack lists a 43 lbs shipping weight. If a technician has to carry the jack between bays, those numbers are the spec that decides it.
Kits, Valves and Hoses for the Flat Bags
A bare ESCO air bag is only the bag. To put one into service you also need a control valve, a hose and a nipple, which is why four kit part numbers are listed in this category (only the 12113K is orderable online today): the 12107K (22 ton), 12109K (32 ton), 12112K (50 ton) and 12113K (70 ton). Each kit page lists the same three companion parts alongside the bag itself: model 12119, a single safety relief and control valve; model 12122, a 20 ft air bag hose with couplers; and model 12123, a nipple and industrial nipple with valve. All three are also listed individually here as replacements. The 22 ton kit is listed at 28 lbs, the 32 ton at 32 lbs, the 50 ton at 49 lbs and the 70 ton at 70 lbs.
Certifications and Warnings
None of the 25 listings in this category declares ALI, ETL, ASME or OSHA certification. ALI certification is a vehicle lift program and does not apply to jacks of this type, so its absence here is expected rather than a gap. What the listings do carry is a California Proposition 65 warning, which appears on every ESCO product page in this category, including all five Maximum Force bags, all four kits, the three service components, all four bladder jacks and the 92017 extension. Safety hardware is stated per model rather than per category: limit stop and safety valve on the ESCO YAK jacks, dual safety valve against over-inflation and uncontrolled descent on the ESCO Pro Series, and an over-inflation pressure relief valve on the iDEAL FR-BagJack.
Model Comparison
| Model |
Brand |
Type |
Capacity |
Min. height |
Max. height |
Air pressure |
Weight |
| 92040 | ESCO | Pro Series double bag, 2 stage | 2 tons (4,000 lb) | 4.5 in. | 9.25 in. (stage B; no combined A+B total published) | 100-145 psi | 34 lbs |
| 92041 | ESCO | Pro Series triple bag, 3 stage | 2 tons (4,000 lbs) | 7.9 in. | 11.8 in. stage B / 22 in. total (A+B+C) | 100-145 psi | 37.4 lbs |
| 92011 YAK | ESCO | Bladder, 2 stage | 2.2 ton | 5.2 in. | 12.83 in. | 116-145 psi | 31 lbs |
| 92013 YAK | ESCO | Bladder, 3 stage | 2.2 ton | 8.07 in. | 19.29 in. | 116-145 psi | 37 lbs |
| FR-BagJack | iDEAL | Bladder, 2 stage | 4,400 lbs | 5 5/16 in. | 13 3/4 in. | 100 psi | 43 lbs ship |
| AJ-2 | Herkules | Double bag | 4,500 lb | 6.5 in. | 13.75 in. (see note) | 90-110 psi | 33 lbs |
| AJ-3 | Herkules | Triple bag | 4,500 lb | 7.875 in. | 19.25 in. | 90-110 psi | 37 lbs |
| GOJ-TBT2 | RakJak / Zendex Tool | Triple bag | 2 ton at 105 psi | 6.875 in. relaxed | 18 in. | 105 psi | 44.5 lbs |
| GOJ-TBT3 | RakJak / Zendex Tool | Triple bag, 12 in. bag | 3 ton (6,000 lb) | see note | 18 in. | not published | 61.75 lbs |
| 12105 | ESCO | Flat air bag, aramid | 13 ton | 1 in. deflated | 7.5 in. | not published | 10 lbs |
| 12109 | ESCO | Flat air bag, aramid | 32 ton | 1 in. deflated | 12 in. | not published | 24 lbs |
| 12113 | ESCO | Flat air bag, aramid | 70 ton | 1 in. deflated | 18 in. | not published | 52 lbs |
The 12105, 12109 and 12113 measure 15 x 15 x 1 in., 15 x 15 x 1 in. and 34 x 34 x 1 in. respectively. The 22 ton 12107 (9.5 in. max, 17 lbs) and 50 ton 12112 (15 in. max, 45 lbs) fill the gaps in the flat bag range.
Where the Listings Disagree
Two specs in this category are inconsistent inside the manufacturer copy, and it is better to know before you order than after.
- Herkules AJ-2 maximum height. The product name states it lifts to 13.75 in.; a feature bullet in the same listing says the raised height is 13 inches. The model name is the more reliable of the two, so treat 13.75 in. as the figure and confirm against the AJ-2 instruction manual linked on the product page if the last three quarters of an inch matter to your job.
- RakJak GOJ-TBT3 minimum height. Its spec table gives a min/max of 6.875 in. / 18 in. in one row and a relaxed height of 7.25 in. in another. The 6.875 in. figure is identical to the smaller GOJ-TBT2 and appears to have been carried over, so plan around 7.25 in. and verify on the model page.
Two listings ship free: the RakJak GOJ-TBT2 and the ESCO 70 ton kit 12113K both carry a Free Shipping flag on their product pages. The iDEAL FR-BagJack page publishes a flat freight charge of $95 per unit to the contiguous 48 states, excluding Alaska, Hawaii and remote or limited-access locations, with a quote required above two units. The remaining listings do not publish a freight figure, so check the individual product page.
Frequently Asked Questions
What air pressure do I need to run an air bag jack?
It depends on the model, and the range in this category is wide. The Herkules AJ-2 and AJ-3 call for 90 to 110 psi of standard shop air, the iDEAL FR-BagJack for 100 psi, and the RakJak GOJ-TBT2 is rated 2 ton at 105 psi. The ESCO Pro Series 92040 and 92041 list 100 to 145 psi and the ESCO YAK 92011 and 92013 list 116 to 145 psi, so a shop regulated at 90 or 100 psi should confirm its supply before choosing a YAK.
What is the difference between a double bag and a triple bag air jack?
Stages, not strength. The Herkules AJ-2 (double bag) and AJ-3 (triple bag) are both rated 4,500 lb, but the AJ-2 collapses to 6.5 in. and the AJ-3 to 7.875 in. while reaching 19.25 in. The same pattern shows in the ESCO Pro Series: the 2 stage 92040 starts at 4.5 in., the 3 stage 92041 starts at 7.9 in. and reaches 22 in. Choose the extra stage when you need height, and the shorter one when clearance under the vehicle is tight.
Do I need a bladder jack or a flat ESCO air bag?
A bladder or bag-and-frame jack is a shop tool for cars, SUVs and light trucks: 2 to 3 tons, a handle and air controls. A flat ESCO Maximum Force bag is a 1 in. thick aramid pad rated from 13 to 70 tons that slides into a gap as small as one inch, and its listings point at material handling, railroad, mining, rescue, military, agricultural and OTR tire work. If your job is wheel, brake or suspension service, you want the first. If you are lifting something heavy with almost no clearance, you want the second.
Does an ESCO air bag come with the hose and valve?
Only if you buy the kit part number. The bare 12107, 12109, 12112 and 12113 are the bag alone. The 12107K, 12109K, 12112K and 12113K kits are listed as containing the bag plus the 12119 single safety relief and control valve, the 12122 20 ft hose with couplers, and the 12123 nipple with valve. Those three components are also sold individually here as replacements.
Can I get more height out of a Herkules AJ2 or AJ3?
Yes. The AJ-X50 (2 in.) and AJ-X100 (4 in.) extensions are both listed for the AJ2 or AJ3, and each notes that the cap is sold separately. The 10454 pinch weld adapter also fits both. For the ESCO YAK jacks, the 92017 is a 2.68 in. extension rated 2.2 ton for the 92011 and 92013. The ESCO Pro Series 92040 and 92041 already include an extension, 3 in. (80 mm) and 2.25 in. (60 mm) respectively.
Can I work under a vehicle held up by an air jack?
Treat every unit in this category as a lifting device, not a holding device. Raise the vehicle, then transfer the load onto jack stands or the rack before anyone goes underneath. Several models publish load-safety hardware for the lift itself, including the limit stop and safety valve on the ESCO YAK jacks, the dual safety valve against over-inflation and uncontrolled descent on the ESCO Pro Series, and the over-inflation pressure relief valve on the iDEAL FR-BagJack, but none of these listings describes the jack as a substitute for stands. If you are not sure which model fits your rack, your clearance or your air supply, call us at 800-562-4791 and we will match the spec sheet to your bay.