- GM-(all Makes and Models Coarse Thread Spare Tire Hold Down Wing Nut, 2 piece. Zinc / Phosphate Plated. Hook the correct length of 8 1/4, Coarse Thread Spare Tire Hold Down Wing Nut, Zinc Plated Factory Correct. 1964-81 GM, 1967-81 F-body / , 1964-72 GM A-body , , , , 1968-1979 , 1971-1974 , 73-74 / , 1965-1978 Fullsize , 1966-1978 All , 1969-1972 , 1965-1978 1965-1978 Fullsize (All Models), This is exact reproduction of the original. This a brand new inline tube factory correct reproduction. is the correct size, shape, Length made from the Metal Plated Silver Zinc Phosphate