8 Pc R8 Collet Set Fractional 1/8" to 1" High Precision for Bridgeport 8 Piece Our Part # ALL-41049 High precision 8 piece set includes 1/8-1" x 1/8" R8 collets Made of high grade tool steel. Hardened and precision ground. Threaded internally 7/16"-20 Guaranteed T.I.R. 0.0005"