A coilover consists of a shock absorber with a coil spring encircling it. This provides for optimal damping without torsional loads. Some coilovers allow adjustment of ride height and stiffness, using a simple threaded spring perch similar to a nut. More advanced adjustable coilover systems will use a threaded shock body, coupled with an adjustable lower mount for ride height adjustment, while an adjustment **** is used to adjust damping, commonly referred to as "stiffness." Spring rate also plays a role in stiffness.

Velocity refers to piston speed.

Compression is low even at high speed. More compression is harsher ride, so this is a relatively comfortable ride even on full stiff at high piston velocity.

Compression is how much the spring is allowed to compress (Bump) and decompress (Rebound).

Restricting the rate at which the front springs are allowed to decompress can help to increase down force and grip in the turns. The bump damping helps control how fast a car takes a set in a corner. The rebound damping helps contain that energy when the spring is trying to push the car body back up. If the rebound was too weak, you would turn into a corner and the car would keep coming back to itself and not maintain a steady state.