Special Features:

Third hole on bearing surface drilled and tapped 0.250-20 unc 2b

Properties:

A nut, circular in shape, which may have wrenching facilities such as flats, holes, protrusions, slots or splines in or on the periphery or in the face opposite the bearing surface. For items having a thickness (or height) exceeding two times the outside diameter, use post, electrical-mechanical equipment. See also nut (1), plain, knurled. (when height or thickness and/or outside diameter is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)