The blocks are precision ground into different angles that can be combined to produce any whole angle of 100 degrees or less.

With an accuracy of +/-0.006 degrees, these blocks are far more accurate than any protractor and roughly 10 times more accurate than the digital angle readouts used in wood shops.

This 10pc set includes precision ground, 3"-long steel blocks in angles of 1 degree, 2 degrees, 3 degrees, 4 degrees, 5 degrees, 10 degrees, 15 degrees, 20 degrees, 25 degrees& 30 degrees. Angles are etched on blocks for easy identification.

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