VARIABLE-SPEED DRIVE ADJUSTER SPRING Silicon-steel springs with high carbon content, heat-treated, dynamically balanced, kiln painted, designed and calculated for each specific application. Malossi Springs can be divided into three categories: REINFORCED SPRINGS with high stiffness (white) SUPER REINFORCES SPRINGS with exceptionally-high stiffness (Yellow) RACING SPRINGS designed for high performance use and competition machines (red) Compatible with: - Aprilia: Area 51_S, Rally 50 AC_S, Rally 50 LC_S, Scarabeo 50 Min.AC_S, Sonic 50 AC_S, Sonic 50 LC_S, SR 50 Min.AC 94-_S, SR 50 Min.LC_S - Beta: Ark 50 AC_S, Ark 50 LC_S - Malaguti: Centro 50 AC_S, F10_S, F12 AC_S, F12 LC_S, F15 Firefox_S - Mbk: Booster 50 euro 0-1_S, Booster 50 euro 2_S, Mach G 50 AC_S, Mach G 50 LC_S, Nitro 50_S, Ovetto_S, Stunt 50 euro 0-1_S, Stunt 50 euro 2_S - Yamaha: AEROX 50_S, BW's 50 euro 0-1_S, BW's 50 euro 2_S, neo's 50_S