Easy To Grip Handles Make This Set Easy To Use.* Set Of 4 Adjustable-size Chuck T-handle Vises For Hand Turning Taps, Drill Bits, Reamers * Hardened & Tempered High-carbon Steel * Fits 3/16"(4.8mm), 3/16-1/4"(4.8mm-6.25mm), 1/4-5/16"(6.25-8mm), 5/16-3/8"(8-9.5mm) *