The KW H.A.S. System (Height Adjustable Spring System) allows you to have the best of both worlds in a spring kit for the lowering your Porsche Turbo or Turbo S. The HAS system allows the installer to choose the desired ride height rather than being stuck with where a fixed spring would wind up. Being able to adjust ride height is especially useful on track by being able to increase or decrease the rake of the vehicle helping to dial in the suspension.
KW H.A.S. Porsche 911 (Type 991) Turbo, Turbo S, with PDCC
Front Lowering: 0.4" to 1.2"
Rear Lowering: 0.0" to 1.0"
See installation instructions here.