1、The best use speed of electric drill is 0-400 rpm. 2、Fits from 1/8\"(3mm) to 3/4\"(19mm). 3、1/4\" hex shank, quick change bit. 4、Made of premium quality high speed steel. 5、It is used for chamfering and deburring of stainless steel, hardened steel, low carbon steel, copper, brass, aluminum, etc. Features: The best use speed of electric drill is 0-400 rpm. Fits from 1/8"(3mm) to 3/4"(19mm). 1/4" hex shank, quick change bit. Made of premium quality high speed steel. It is used for chamfering and deburring of stainless steel, hardened steel, low carbon steel, copper, brass, aluminum, etc. Specifications: Material: Steel Item Size: 50 * 36 * 36mm / 1.97 * 1.42 * 1.42in Item Weight: 126g / 4.47oz Package Weight: 133g / 4.71oz Package Size: 5 * 5 * 5cm / 1.97 * 1.97 * 1.97in Package List: 1 * Deburring Drill Bit 1 * Deburring Drill Bit