Promate 2 Lens Pro Slender Mask with Nose Purge Scuba Diving Mask - Optional Prescription Lens Options Available. (Detailed lens info at Item code RX002). Features: Ideal for medium faces Patented purge design Patented channeled skirt design directs bubbles away from view Crystal, liquid silicone injected skirt and strap Double edge comfort seal Low volume Swivel and adjustable buckles Broad peripheral view Tempered glasses Optical lenses available from -1.0 to -10.0 by increments of 0.5 (for near sighted) Optical lenses available from +1.0 to +4.5 by increments of 0.5 (for far sighted) Made in Thailand Please note there will be an additional 2 to 3 days processing time for most RX lenses This Quality Scuba Diving Mask is a fantastic state of the art mask which is ideal for comfort and performance! Good for scuba diving and/or snorkeling. Returns are not accepted for used lens. Only unused lens are eligible for return with store credit.