This precision 24" 600 mm English Metric satin chrome “zero glare” combination square blade is made in the USA by Products Engineering Company (PEC Tools), a premier tool manufacturer. Guaranteed to interface with Starett, Mitutoyo, PEC and Brown and Sharpe combination squares. This blade is made from hardened tool steel and is 1.00” wide by .090” thick with a groove down one side. It has a “zero-glare” satin chrome finish that provides better rust and scratch resistance than polished steel and can be easily read in both low and bright light conditions. All 4 sides of each blade are ground parallel and straight. English metric graduations have 1/64 and .5 mm on one side and 1/32” and mm on the other. Graduations are deeply precision photo etched and then black filled for easy readability.