MS21042 & NAS1291 Style B Nuts

Inspec100 is proud to offer a design solution to MS21042 and NAS1291 nuts. These nuts are widely used throughout the aerospace industry and have gained a reputation for failure due to hydrogen embrittlement. However, this is a misconception, the actual failure mode is due to nut dilation. The revolutionary new shape of the style B design enables these nuts to meet the same mechanical properties while lowering HRC hardness requirements. The result is a light weight, low height, self locking hex flange nut that reduces the likelihood of failure due to nut dilation.

By adding LT onto the style B product line buyers can specify a low torque variant:

MS21042 / NAS1291 Style B

To obtain a manufacturing license email Free samples are available on request from