What is the offset when using a conduit bender?

The offset is the preset distance that is marked on the shoe of the bender. This preset mark allows for shrink back when bending. It allows you to make a perfect bend if a conduit run comes to a wall and has to go up the wall. It takes into account the outside diameter of the conduit and adds it to the shrink back of the bend to make the conduit fit exactly up against the 90 degree angle of the wall.

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