These are Nylon Insert Lock Nuts from Du-Bro. FEATURES: Zinc plated, aircraft quality steel construction. Plum colored nylon insert. INCLUDES: (4) Lock Nuts SPECS: Thread Size: 4-40 EtH 6-14-94 kr3/17/03 BOX DIMENSIONS: 2.25″ W. X .25″ H. X 2.25″ L. BOX WEIGHT: .02 LBS.
