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- IMPROVES RIDE – The Flex Air 5th wheel pin box combines our time-tested Air Ride technology with our Rota-Flex pivoting head to significantly reduce fore to aft movement and vertical tug-of-war between a 5th wheel RV and tow vehicle
- INNOVATIVE STRUCTURE – This pin box contains an internal air bag that moves in a scissor-like motion to absorb vibrations, a rubberized compound to soften jarring movement, and an oil shock absorber to handle rebound action, dampen kickback and control chucking
- SIMPLE INSTALLATION – The Flex Air is ready to be installed as soon as it comes out of the box. It uses the same bolts as the original pin box, so no additional hardware is needed for installation
- BUILT TO LAST – Constructed with steel and a black powder coat finish that protects against rust, this pin box is extremely long-lasting to ensure peaceful towing day after day
- SPECIALLY DESIGNED – The Flex Air is specifically configured to replace Lippert 1621 5th wheel pin boxes with a towing capacity of 21,000 lbs.
With the Flex Air® Pin Box by CURT®, you can stabilize your 5th wheel trailer or RV with ease. The Flex Air boasts an internal air bag and built-in strut that team up with a rubberized pivoting head to reduce chucking and virtually eliminate bounce and jarring. The pivoting head regulates movement of the king pin within the hitch while the rubber compound absorbs road shock, giving you a smooth ride that keeps things in control through harsh roads. Leave unwanted movement right at home!
The Flex Air uses innovative technology to ensure your towing experience is superior. It utilizes an internal air bag that moves in a scissor-like motion to absorb vibrations, a rubberized compound to soften jarring movement, and an oil shock absorber to handle rebound action, dampen kickback and control chucking. The Flex Air 5th wheel pin box combines our time-tested Air Ride™ technology with our Rota-Flex™ pivoting head to significantly reduce fore to aft movement and vertical tug-of-war between a 5th wheel RV and tow vehicle.
Towing 21,000 lbs. never felt so good! The Flex Air is designed to replace Lippert 1621 pin boxes and has a 21,000 lb. gross trailer weight (GTW). It comes ready to install and uses the same bolts as the original pin box, so it doesn’t require any additional hardware for installation. Constructed with high-strength steel and finished with a black powder coating, the Flex Air is the ultimate 5th wheel pin box to tackle your towing needs for the road ahead.
- Replaces Lippert 1621 5th wheel pin boxes
- Reduces chucking and absorbs road shock
- Long jaw with pivoting head
- Features Air Ride™ technology
- Bolt-on installation with no assembly required
- Constructed with steel and a black powder coat finish that protects against rust
- 21,000-lb. towing capacity
- Made in the USA
| Finish | Black powder coat |
|---|---|
| Material | Steel |
| Width (inches) | 16 |
| Height (inches) | 19 |
| Length (inches) | 41 |
| Weight (pounds) | 258 |
| Towing capacity (pounds) | 21000 |
- What towing capacity does the curt l05 flex air 5th wheel pin box support? The Curt L05 Flex Air 5th Wheel Pin Box supports a towing capacity of 21,000 lbs.
- Is the curt l05 flex air compatible with lippert 1621 pin boxes? Yes, the Curt L05 Flex Air is specifically designed to replace Lippert 1621 5th wheel pin boxes.
- Does this pin box help reduce road vibrations and chucking? Yes, it features Air Ride technology with an internal air bag, a rubberized pivoting head, and an oil shock absorber to significantly reduce chucking and absorb road shocks.
- Is installation complicated or requires special hardware? Installation is simple and bolt-on using the same bolts as the original pin box, so no additional hardware or assembly is required.
- What materials and finish are used for durability in this pin box? The pin box is constructed with high-strength steel and finished with a black powder coat to protect against rust and ensure long-lasting durability.
Factory-Fresh OEM Parts — the same brands installed in new RVs straight from Elkhart. Genuine, name-brand components made to order — never generic, never outdated. Sourced directly from the original RV manufacturers for perfect fit and factory-level quality.