 Authorities disagree on whether nyloc nuts should be reused.For example, Carroll Smith ("Carroll Smith's Nuts, Bolts, Fasteners, and Plumbing Handbook") notes that the nylon insert is not damaged by installation and therefore they can be reused many times, and a Federal Aviation Administration Advisory Circular allows nuts to be reused if the prevailing torque is within specification.However, a United States Air Force Technical Order requires replacement of self-locking nuts in critical areas.