【Three-Jaw Chuck】Alloy material, One-piece structure design, sturdy and durable, more safer than plastic models. The three-jaw chuck can hold these tiny bits more securely at high speeds, and the built-in spring is stable and durable. Quick change keyless chucks holds various accessories with 1/32” to 1/8” shank sizes 【Metal Change Collet Nuts】Alloy steel material, wear-resistant, more durable and safe than other plastic materials. Use with brass collets, Strong adaptability, lmproved accuracy 【Brass Nut Set】Made of high-quality brass material, tough, more sturdy and durable, not easy to bend, 4 Claws design and workmanship ensure strong holding power and hold the drill bit more firmly, more size of clamping diameter make them more versatile 【Strong Compatibility】Drill chuck collet set compatible with most rotary tools you meet on the market. Easy and quick to change accessories without changing rotary tools, including drill bits, buffing wheels, three-edged sharp knife, cut-off wheels, and more 【Package Content】You will get 28pcs drill chuck collet, including replacement keyless chuckX2, metal collet nutX4, brass 4485 colletsX20, super-thin open end wrench X1, L-wrench X 1. (Tips: Please check the size before buying）