Bracket uses a 3/8-16" shcs grade 8 bolt for mounting. This bracket is polished then anodized black and racer must read below to pick the proper bracket for there application.
TBS/Littlefield blower snout O.D. of 3.430" with 5/8-18" threads to mount the idler pulley.
BDS blower snout O.D. of 3.370" with 5/8-11" threads to mount the idler pulley. If unsure of what brand of blower snout you have slip a pair of dial calipers over the snout housing so you will get the right part the first time. There is a small amount of adjustment for different size blower snouts.
Buyer can pick snout diameter size from drop down menu.