Description: These bit holders and extension adapters are made of high-quality carbon steel and chrome vanadium steel with a robust construction to ensure maximum durability. They can be used for both drills and bits, making these extension adapters very practical and versatile. Features: Carbon steel adapter for maximum durability, robust construction allows for long service life. Ball detent design for quick connection or disconnection and ensures it stays in place during operation. Universal SDS plus shank fits many power drills and chucks. The small size allows you to take your bit extension wherever you go to perform any job and it fits in many tool bags. There is one hex shank and three square adapters in different sizes and you can use the appropriate one for different needs. Specifications: Material: Stainless steel and chrome vanadium steel Type: SDS Plus - 80mm x 1/4\" hex shank, SDS Plus -- 65mm x 1/4\" square head, SDS Plus - 65mm x 3/8\" square head, SDS Plus - 75mm square head x 1/2\" Quantity: 4 Package includes: 1 x Hex Shank Extension Adapter 3 x Square Extension Adapters 1, Hard steel adapter for maximum durability, robust construction allows for long service life 2, Ball detent design for quick connection or disconnection and ensures it stays in place during operation 3, Universal SDS Plus shank fits most electric screwdrivers, drills and chucks. 4. The small size allows you to take your bit extension wherever you go to perform any job and it fits in many tool bags. 5. There is one hex shank and three square adapters in different sizes and you can use the appropriate one for different needs.