aluminum alloys and special steel Primary spring: 125 mm Evoluzione diaphragm spring code 003SUZ119 Secondary spring: 85 mm Evoluzione spring code 0F3SR540B140006 Basket: original Suzuki (not included) Features: slipper system - device to control the opening Forced Lubrication System 2 Compatible disc pack: original (not included) Tools: pressure plate mounting tool code 002AMS001 (recommended) Note: when choosing the primary spring keep in mind that the greater the spring tension, the greater the pressure on the disc pack and the smaller the slipping in acceleration.