【Durable】Quenched and heat treated S2 alloy steel bits, hardness arrived at 58-60 HRC, reduce wear-outs. 【Ideal Tools】Use with ratchet to improve speed in tightening spline drive fasteners. Bit: Drop-forged, Heat-treated S2 alloy steel, durable to use with its high hardness (58-60 HRC).
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