Sherwood: 5/16"X18 UNC HSS Hexagon Die Nut BS 1127. For use with spanners to clean and repair existing external screw threads. MPN: 5036140184077 EAN: 5036140184077 5/16"X18 UNC HSS Hexagon Die Nut Attributes: Dimensions Standard: BS 1127 Hex Width: 0.82in Material: High Speed Steel Thickness: 5/16in Thread Direction: Right Hand Thread Size: 5/16in. x 18 Thread Standard: UNC