M.A.S.S. Spare Tire Platforms: Put the Space Above Your Spare to Work
AAL invented the M.A.S.S. Spare Tire Platform around a simple observation: a rear-mounted spare occupies a large part of the back of the vehicle, but the space above it usually carries nothing. The STP turns that space into an exterior cargo deck for camp gear, recovery equipment, firewood, dry boxes, and other equipment you would rather keep out of the cabin.
M.A.S.S. stands for Modular Adaptable Storage System. It is the design concept we carry through our products: keep the structure lightweight, give customers flexible ways to configure it, and make each setup adaptable to the vehicle, cargo, and trip instead of forcing every customer into the same fixed solution.
Both M.A.S.S. platforms strap to the spare tire instead of drilling into the vehicle body. That lets the platform follow the tire carrier and makes fitment depend on the tire, available clearance, and carrier capacity rather than one specific Jeep, Bronco, or off-road vehicle body.
Full-Size STP vs. STP Mini
Choose the full-size STP for most 33- to 40-inch tires and the largest cargo deck. Choose the STP Mini for most 27- to 35-inch tires, angled spare carriers, or builds that need a smaller rear footprint.
| Compare | Full-Size M.A.S.S. STP | M.A.S.S. STP Mini |
|---|---|---|
| Best Match | Larger spare tires and customers who want the largest available cargo deck | Smaller spare tires, angled carriers, and builds with tighter rear clearance |
| Typical Tire Diameter | 33ā40 in | 27ā35 in |
| Interior Cargo Area | 42 Ć 19.125 in | 38.5 Ć 16.75 in |
| Tire Fitment Detail | Requires a tread patch wider than 9.7 in | Designed around the smaller tire range; verify tire, carrier, and rear-glass clearance |
| Angled Spare Support | The Mini may be a better match for angled carriers | Optional Camber Kit can level the platform |
| Construction | 1/8-in 5052 aluminum, Made in USA | 1/8-in 5052 aluminum, Made in USA |
| Mounting Approach | Straps around the spare and laterally through the wheel | Straps around the spare and laterally through the wheel |
| AEV Fuel Caddy | Not compatible | Not compatible |
| Product | View the Full-Size STP | View the STP Mini |
Built Around the Tire, Carrier, and Cargo
We build both platforms in the USA from 1/8-inch 5052 aluminum. Slots and mounting points provide useful places to secure cargo and add compatible accessories without turning the rear of the vehicle into a pile of improvised brackets.
- Check the tire size: the full-size STP is intended for most 33- to 40-inch tires with a tread patch wider than 9.7 inches; the Mini is intended for most 27- to 35-inch tires.
- Check the carrier: the spare-tire carrier supports the spare, platform, accessories, and cargo together. A sturdy swing-out carrier is the best foundation for a loaded platform.
- Check clearance: verify the third brake light, tire angle, rear glass, and any fuel-caddy or carrier accessories before choosing a platform.
- Secure it correctly: use circumferential and lateral restraint. Routing the lateral straps through the wheel is the preferred setup.
Choose the platform that matches your tire and carrier, then open its product page for complete dimensions, load guidance, finish choices, and accessory options.
Cargo Management
M.A.S.S. Spare Tire Platform (STP)
Best for 33 to 40 Inch Tires
Choose the Full-Size STP when usable deck space is the priority.
Its 42 Ć 19.125 inch interior cargo area fits most larger spares and supports up to 50 pounds of evenly distributed cargo, subject to the tire carrier’s lower limit.
Cargo Management
M.A.S.S. Spare Tire Platform Mini (STP Mini)
Best for 27 to 35 Inch Tires
Choose the STP Mini for tighter rear clearance or an angled spare carrier.
Its 38.5 Ć 16.75 inch interior cargo area keeps the rear footprint compact. Add the optional Camber Kit when the spare sits at an angle and the platform needs to be leveled.