These are the original exhaust studs used on the V-8 engine for trucks that does not use a heat riser valve or spacer. It has an overall length of 2 7/32. It takes 3 total. Use nut number 86-040 with these. If not using a spacer or valve use this stud on both sides and a total of 6. If needing a heat riser use part number 89-424.