See Beryllium Copper Tolerances
Beryllium Copper Round Bar 173 offers strength comparable to alloy steel, excellent corrosion resistance, fatigue resistance, high workability, and machinability. 173 is also known as free machining beryllium because it maintains the strength of other beryllium coppers but is easier to machine. It is typically used for springs, flexible metal hose, washers, retaining rings, bushings, valves, firing pins, navigational equipment, and non-sparking safety tools.
This bar comes in a hard temper and unpolished mill finish.