Bit set shank: 6.35mm/1/4", Length: 100mm(3.94"). 100mm(3.94") length, longer than the market ones, More practical and convenient. 10pcs Screwdriver Bits. 【Professional Hex Bit Set Are Made of Alloy Steel, Very Well Made And Tough As Nails】 - Hardness can reach HRC60 degree.
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