This is the Tusa Freedom Tri-Quest 3-Window Panoramic View Wide Angle Scuba Diving Snorkeling Mask Features: Expanded panoramic view through 1-window lens New Design - Patented domed side windows Reduced frame structure to reduce blind spots Equipped with Freedom Technology Three-dimensional strap for unprecedented fit Five-position strap angle adjustor for micro-adjustment The M3001 Freedom Tri-Quest Mask features Freedom Technology with newly designed patented domed side windows and an expanded panoramic view through a 1-window lens. The Tri-Quest Mask has a reduced frame structure to reduce blind spots and a three-dimensional strap for an unprecedented fit.