The Hillman Group 59038 Nylon White Cap Colored Pushnut, 1/2-Inch, 10-Pack, Model: 59038 (Tools & Outdoor gear supplies)

A Push Nut has no threading but has an inward facing flange. The flange is meant for quick assembly ,no tools needed, and the nut can be pushed into place. A push nut has a wide flange at one end that acts as an integrated, non-spinning washer. This serves to distribute the pressure of the nut over the part being secured, reducing the chance of damage to the part and making it less likely to loosen as a result of an uneven fastening surface.