Rollers are made from bearing steel (JIS SUJ-2/SAE 52100/DIN 100 Cr6) and have been subjected to heat treatment and precision grinding radius diameter deviation the hardness is HV700-860 (HRC60-66). All the raw material comes from Japan directly. High-purity Chromium Molybdenum alloy steel (JIS SCM415) with Carbon Nitriding heat treatment process. The hardness specification is approximately HV500 to HV600; it always can meet the requirement of high-speed engine applications. Heat treated and ground to precision tolerances for reduced heat and extended life. 18mm x 22mm x 22mm (ID x OD x L) This item fits H-D the following vehicle applications: fits Arctic Cat™ Mountain Cat 800 2001-2002 fits Arctic Cat™ Mountain Cat 800 EFI 2002 fits Arctic Cat™ Mountain Cat 800 EFI 144 2003 fits Arctic Cat™ Mountain Cat 800 EFI 151 2003-2004 fits Arctic Cat™ Mountain Cat 800 EFI 159 2004 fits Arctic Cat™ Mountain Cat 800 EFI LE 144 2002 fits Arctic Cat™ Mountain Cat 800 EFI LE 151 2002 fits Arctic Cat™ Pantera 800 EFI 2004 fits Arctic Cat™ ZL 800 EFI ESR 2002-2003 fits Arctic Cat™ ZL 800 EFI SS 2002-2003 fits Arctic Cat™ ZR 800 2001-2002 fits KAW SST 340 1977 fits KAW SST 440 1977 fits YAM BR250 Bravo 1992-1993 fits YAM BR250 Bravo 1982-1990 fits YAM BR250T Bravo LT 1992-2000 fits YAM BR250T Bravo LT 1990 fits YAM BR250T Bravo T 1991 fits YAM BR250T Bravo T 1987-1989 fits YAM ET250 1977-1981 fits YAM ET410TR Enticer II LT 1994 fits YAM EX340 1977-1978 fits YAM EX440 1977-1981 fits YAM GP440 1976-1977 fits YAM GS300 1977 fits YAM GS340 1976-1977 fits YAM PR440 1976 fits YAM PZ480 Phazer 1984-1989 fits YAM PZ480 Phazer II 1990-1993 fits YAM PZ480E Phazer E 1985 fits YAM PZ480E Phazer II LE 1990-1996 fits YAM PZ480E Phazer SS Electric 1997-1998 fits YAM PZ480SE Phazer SE 1984 fits YAM PZ480ST Phazer II ST 1991-1995 fits YAM PZ480ST Phazer Mountain Lite 1996-1998 fits YAM PZ500 Phazer 500 1999-2000 fits YAM SRX340 1976 fits YAM SRX440 1976-1977 fits YAM SS440 1980-1985 fits YAM VT480 Venture XL 1994-1997 fits YAM VT500 Venture 500 1999-2000