Features:- Used for supporting of round and square jobs during Light machining, Grinding, Drilling & Inspection. Accuracy for Flatness, Squareness and Parellelism within +0.0005 mm. Hardness 60+2 Rc. Supplied in perfect matched pair. Supplied with clamp. Can also be used for end face, side face and right angle Grinding. SIZE:- 25 L X 20 W X 20 H [ 1" ] 50 L X 40 W X 40 H [ 2" ] 80 L X 63 W X 63 H [ 3" ] 100 L X 80 W X 80 H [ 4"