The Dock Edge Dolphin Roto-Molded Fender is manufactured from the best quality marine-grade vinyl, resulting in superior strength, cushioning, and a high-gloss finish. Tested for many years in various marine environments worldwide, the Dolphin Fender resists deterioration from mildew, gas, oil, seawater, and bacteria and has built-in ultraviolet inhibitors. This fender includes an inflation valve to allow for adjustment to the desired level of firmness. Resists deterioration from mildew, gas, oil, seawater, & bacteria Built-in ultraviolet inhibitors resist fading Inflation valve allows easy adjustment to desired level of firmness | Dock Edge Dolphin 8.5" x 27" Twin-Eye Smooth Boat Fender, Royal Blue