These wheel lug studs are made of carbon steel and tested to demanding automotive industry standards to ensure strength, longevity and safety.Vehicle model years this part fits:Chevrolet C30 Pickup: 1971, 1972, 1973, 1974 Chevrolet C30: 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986 Chevrolet G30 Van: 1972, 1973, 1974 Chevrolet G30: 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996 Chevrolet P30 Van: 1971, 1972, 1973, 1974 Chevrolet P30: 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999 Chevrolet R30: 1987, 1988 Chevrolet R3500: 1989, 1990, 1991 GMC C35/C3500 Pickup: 1971, 1972, 1973, 1974 GMC C35: 1975, 1976, 1977, 1978 GMC C3500: 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986 GMC G35/G3500 Van: 1972, 1973, 1974 GMC G35: 1975, 1976, 1977, 1978 GMC G3500: 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996 GMC P35/P3500 Van: 1971, 1972, 1973, 1974 GMC P35: 1975, 1976, 1977, 1978 GMC P3500: 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999 GMC R3500: 1987, 1988, 1989, 1990, 1991