1. We are here to provide Sioux Valve Seat Grinder Kit Sioux Style which Includes 12 pieces Sioux Stones + 6 Pcs Sioux Pilots + 2 sets of Sioux Stone Holder & Drive ball. 2. Verified Bond 80 Grit Medium Alminium Oxide Pink Stones (Stones angle 45 degree) from 25.4MM (1") to 63.5MM (2-1/2") stone sizes: 2-1/2" - 1 PCS, 2-3/8" - 1 PCS, 2-1/4" - 1 PCS, 2" - 1 PCS , 1-7/8" - 1 PCS, 1-3/4" - 1 PCS, 1-5/8" - 1 PCS, 1-1/2" - 1 PCS, 1-3/8" - 1 PCS, 1-1/4" - 1 PCS, 1-1/8" - 1 PCS 1" - 1 PCS STONE THREAD - 11/16" 3. Sioux Valve Seat Grinder Straight Pilots set Sioux Valve Seat Grinder Straght Pilots set of 6 Pcs set TOP .385" STEM SIZES 4.5mm + 5mm + 5.5mm + 6mm + 7mm + 8mm. 4. 2 X of Heavy duty Sioux valve seat grinder stone holder thread of 11/16" inches with 2 pieces of drive ball. 5. Buyer can ask us to modify the pilots sizes and we can make it for you.