2" Boring Combo Set Includes Head R8 Shank & 1/2" Bars Kit for Bridgeport Mill

R8 shank features: 7/8"-20,made of high grade tool steel, hardened & ground, 7/16"-20 internal thread drawbar end. 2" Boring head features: 0.002" graduation, 5/8" max offset, up to 1/2" tool capacity, bar holder moves freely & smoothly, rigid design for precise hole size accuracy.

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