All parts made of hardened tool steel and ground to highest accuracy. Squareness and parallelism are within .0002" per 5". Many 1/4"-20 tapped holes to facilitate clamping. One end rail. .200" step built into gage block roll so that gage blocks over .200" can be used to set very small angles. 5" distance between center rolls is accurate within .0002". Two offset hinges for added stability.
