The S3 sintered compound is optimal for street bikes, dual sport, touring, cruisers. It's recommended on applications with rather larger engines or for people who ride harder than average and want the great stopping power of a sintered brake pad. Fits: Kawasaki Z1000A 1977-1980 Z1000H 1974-1975 Z1000ST 1979-1980 Z1300 1978-1989 Z1R 1978-1980 Z500 1979-1980 Z650D 1978-1981 Suzuki GS1000 1978-1981 GS1000G 1980-1981 GS1000S 1979-1980 GS1100 1982-1985 GS1100GK 1982-1986 GS1100GL 1982 GS550E 1978-1982 GS550L 1979-1980 GS550M KATANA 1981-1983 GS650 1980-1982 GS650G KATANA 1981-1984 GS650GL 1981-1982 GS750 1977-1979 GS750S 1982 GS850G 1979-1985 GSX1000S KATANA 1981-1984 GSX1100 ESD 1980-1983 GSX1100 ET 1980-1983 GSX1100 EX 1980-1983 GSX1100 EZ 1980-1983 GSX1100ES 1983 GSX1100S KATANA 1981-1984 GSX250 1980-1981 GSX250ES 1982-1987 GSX400F 1982-1983 GSX750E 1980-1982 GSX750ES 1983-1985 GSX750S KATANA 1982-1985 XN85 1983-1986