These are the same billet aluminum arms supplied with our Kart Exhaust Pipe Mount Cradle Kits (Part Nos. 9922-001, 9922-002, 9922-003, and 9922-007. Each black anodized bracket measures 1/4" (6mm) thick x 3/4" (19mm) wide, with holes for 8mm or 5/16" bolts.
Short arm measures 74mm long with a single hole at each end.
Medium arm measures 112mm long with a single hole at one end and 3 holes at the other.
Long arm measures 170mm long with a single hole at one end and 3 holes at the other.