A _______ nut has deformed threads or a nylon insert to produce interference during tightening.

• A. Hex Nut
• B. Lock Nut
• C. Cap Nut
• D. Wing Nut

Answer: (B)

Locking nuts are designed to resist loosening by creating interference with the bolt threads. They achieve this either with a nylon insert that grips the threads as you tighten, or by deforming the threads so the nut must overcome that interference, producing a prevailing torque that helps prevent loosening from vibration. A standard hex nut has normal threads without any locking feature, a cap nut is just a cover, and a wing nut is intended for easy hand tightening without locking capability. So the nut described with deformed threads or a nylon insert to produce interference is a locking nut.