Custom manufactured for Dive Gear Express, both DGX Hi-Viz and DGX Ultra-Viz™ lines are round braided polyester with a diameter of approximately 1.8mm and are engineered high-tech products with exceptional strength, abrasion and UV resistance. The only difference is the Ultra-Viz line includes a retroreflective nylon strand impregnated with tiny glass micro-beads (<100 microns) that makes the already vibrant line even brighter. Similar to the way SOLAS tape works, when light shines on the reflective strand the light retroreflects back toward the source of the light, thus further increasing visibility.