PC D RING HALF & HALFPC D RING HALF & HALF This D ring is made from 5 16" diameter material and has an outer diameter of 2 7 8". This D ring is slightly more compact than a normal 3 1 2" D ring. The 5 16" material adds a little more weight which helps the stability and release. The two piece half and half mouthpiece combines a twisted wire bar piece and smooth mouth across the tongue. This mouthpiece is softer than a complete twisted wire. PCB 982