The Hot Cams Valve Shim Kit is a must for any motorcycle to keep it running at full power. Hot Cams includes an labeled organizer to ensure accurate shim replacement. 7.48 mm and 9.48 mm kits: Include three (3) shims for each size ranging from 1.20 through 3.50 mm in 0.05 mm increments. 8.90 mm kit: Includes three (3) shims for each size ranging from 1.72 through 2.60 mm in 0.05 mm increments. 10.00 mm kit: Includes three (3) shims for each size ranging from 1.85 through 3.25 mm in 0.05 mm increments. 13.00 mm kit: Includes three (3) shims for each size ranging from 1.85 mm to 3.20 mm thickness in 0.05 mm increments. Note: Most 250cc 4-strokes use 7.48 mm OD shims, most 400cc and up 4-strokes use 9.48 mm OD shims, and KTM models use 10 or 8.90 mm OD shims.