AP
The AP range here is suspension, sold under the AP Sportfahrwerke name: lowering springs, spring-and-damper kits and coilovers. With one line of each, the choice is simple. It comes down to springs if you want a lower stance on your existing dampers, a kit if the dampers need replacing as well, or a set of coilovers.
The parts are listed mainly for Volkswagen, BMW and Audi, followed by Seat, Skoda and Opel, with Ford, Peugeot, Alfa Romeo, Renault, Fiat and Honda also covered. The listings reach back further than most. Alongside recent cars such as the Audi A3 (8V), Volkswagen Golf VII and Seat Leon (5F), they include the BMW 3 Series E30 and E36.
Compared with the larger spring and coilover ranges here, AP keeps things compact. It is therefore a straightforward place to start if you want a set of springs or a kit without working through several product lines.
Please note that this AP is the suspension brand, not the brake and clutch maker AP Racing.