The Milwaukee 48-66-3080 is a 3/8 in. Chuck Key — a replacement tightening key for Milwaukee corded drills and drill presses equipped with a keyed 3/8 in. drill chuck that requires a chuck key for bit installation and removal. Keyed drill chucks use a rack-and-pinion mechanism that is engaged and turned by the chuck key's bevel gear to tighten or loosen the chuck's three jaws uniformly around the bit shank — the key's bevel gear engages holes around the chuck's circumference and the key handle provides the mechanical leverage to tighten the jaws to the clamping force needed for secure bit retention during drilling. Without the chuck key, bits cannot be changed in a keyed chuck — the chuck key is a required tool for every bit change on keyed chuck drills, making a replacement key immediately necessary when the original is lost or damaged.
- 3/8 in. chuck key for Milwaukee keyed 3/8 in. drill chucks — required for every bit change
- Bevel gear sized and matched to 3/8 in. chuck gear geometry for correct engagement
- Quality steel construction for durability through professional use tightening cycles
- T-handle provides comfortable grip and adequate tightening mechanical advantage
- Always remove from chuck before starting drill — serious safety hazard if left inserted
