They flip the position of the leaf spring and axle so that the springs move from beneath the axle to the top. 1999-2007 Chevy Silverado 1500. When flipping the axle and leaf spring, it’s important to consider shorter shocks or shock extensions.
6" Lowering Drop Flip Kit No C-Notch For 99-06 Chevy Silverado&Sierra 1500 STEEL
6" Lowering Drop Flip Kit No C-Notch For 1999-2006 Chevy Silverado& Sierra 1500
6" Lowering Drop Flip Kit No C-Notch Fits 99-2006 Chevy Silverado & Sierra 1500
6" Lowering Drop Suspension Flip Kit No C-Notch For 99-06 Chevy Silverado 1500
6"-7" Rear Axle Lowering Drop Flip Kit for Chevy Silverado GMC Sierra 1500 07-18
6" Lowering Drop Rear Axle Flip Kit For 1999-2006 Chevy Silverado & Sierra 1500