This specification covers the requirements for standard-type needle roller bearings with drawn outer rings, full complement, without inner rings, and with either open (Type B) or closed ends (Type M). Materials covered by this specification are needle rollers which shall be manufactured from steel, alloy, or carbon, and shall be of Grade E50100 or E52100. Rings, on the other hand, shall be manufactured from steel, alloy, or carbon, with carburizing grade 4620, 4720, 8620, 8720, or 1010-1020. Needle rollers and rings shall be hardened by heat treatment, and bearings shall be coated with rust preventive film.

1.1 This specification covers standard-type needle roller bearings having drawn outer rings, full complement, without inner rings, with either open or closed ends.

1.2 The use of recycled materials that meet the requirements of the applicable material specification without jeopardizing the intended use of the item is encouraged.

1.3 The inner rings specified in this specification are not intended for use in flight critical systems of aircraft.

1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

Note 1: This specification contains many of the requirements of MS17131, which was originally developed by the Department of Defense and is currently maintained by the Defense Supply Center Richmond.