UM29 Freediving Adult Mask The UM29 snorkeling and freediving mask is an ultra low volume mask that offers a minimal air gap The lightweight Polycarbonate lenses have been treated with an anti fog process to prevent fogging The soft silicone skirt incorporates TUSA s quick adjust rear buckle system FEATURES Pure Silicone skirt strap Low profile design Super anti fog treatment UV protection Quick fit rear buckle system