The Factory Race Series 3.0 Internal Bypass shock delivers race-dominating, position-sensitive damping technology and performance in a hassle-free bolt-on kit. Patented, position-sensitive internal bypass technology contains regulated ports that allow fluid to bypass the Piston as it moves through the initial Travel, and then forces fluid through the Piston at the extreme ranges of compression and rebound. This allows for a plush, predictable ride over normal off-road driving conditions with the ability to ramp up damping force to counteract harsh bottom-outs or top-outs that could buck you off the trail. These hard-anodized, aluminum-bodied shocks are engineered with precision-machined aluminum Components and race-bred internal Valving. They are designed to bolt onto your 3.5-4.5 aftermarket suspension lift kit using OEM shock pivots. Featuring a New heavy-duty piggyback bridge designed specifically for Wrangler JL featuring hard-anodized Features Performance Tuned For Vehicle Specific Application, Aluminum Body Dissipates Heat Faster Than Steel, Multiple Internal Damping Zones, External Reservoir System Dissipates Heat Fast, Black Anodized CNC Machined Aluminum Components Series Factory Race Travel 9.41 Rear Lift Height 3.5-4.5 Extended Length 28.34 Compressed Length 18.93 Top Mount ES6 Bottom Mount ES6