Bosch 3-Jaw Keyless Chuck with SDS-Plus Shank, 1/2-Inch HA3JAW EFFICIENT: The Bosch HA3JAW Keyless Chuck is efficient and convenient by quickly locking bits into place. COMPATIBILTY: The three-jaw chuck is built for use with SDS-plus hammers and straight shank drill bits DURABLE: The HA3JAW is built with a steel metal sleeve for maximum rugged durability. QUALITY: Bosch makes the highest quality rotary hammer accessories