Safely compress your tall 3" and 5" springs so that you can install the spring without moving the coil over adjustment nut. The floating plate has a slot that captures the nut so you don't need a wrench. Simply use an impact on the other end of the compressor to compress the spring and install your shock. Compressor also has a slot in each plate for on the car compressing to make quick suspension adjustments and to clamp on a coil over slider in a spring smasher to take to the car for installation.