A series on concentric grooves or rings on a nail or pin to improve the holding power. Commonly used for fixing floorboards, the rings along the body of the nail help to prevent it from working loose with the movement in the floor. The image below shows an annular ring nail, these are available in various lengths and can be purchased using the following link: annular ring nails
Annular Ring Nail

Copyright © 2019 - Door Furniture Direct. All Rights Reserved.