11 PC R8 Collet Set 1/8" to 3/4" for Bridgeport with R8 Collet Rack - 12 slot Our Part # ALL-41080 Includes 11 piece set: 1/8-3/4" x 1/16" collets and R8 collet rack Made of high grade tool steel and hardened and precision ground Threaded internally 7/16"-20 Guaranteed T.I.R. 0.0005" (or better)