I wouldn't call it a "precision parallel set" as nothing is parallel and inaccurate (or accurate). None of the items meet the specifications. For example, a 1 inch pair was 1.0021, 1.0024, 1.0018, and 1.0020. Not parallel and not equal. Vise, they would be fine Only the long side is machined, the short side is not. There are small burrs, mainly on the corners. Do not buy if you do precision machine work.