Hardened Alloy Steel Knurls. Hardened EN31 Grade Tool Steel Knurls of size - 3/4" x 3/8" x 1/4" bore. Clamp Type Knurling Tool with knob. Self-centering Knurling Tool Holder features a knurling head that rotates within a 40 degree arc so equal pressure is automatically applied to both wheels.
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