The SKIL 15-Piece Hex Shank Twist Drill Bit Set includes 15 twist drill bits with ¼-inch hex shanks for use with both drills and impact drivers. The bits have a 135-degree split angle for fast and no-slip drilling, and their black and golden oxide coating provides long-lasting bit life. The bits are packed in a SKIL modular bit case system for easy customized layouts, interlocking functions for stacking out your combination, and auto-connect snap latches for convenient one-handed use.