Promate Hawk Eyes Scuba Dive Mask / Prescription RX lens Available ProMate Sea Viewer Scuba Dive Mask (Rx-Able) / MK270: Require PRESCRIPTION by email to info@getwetstore.com or fax to (866)422-4584. You may check optical lenses (OP270) at Amazon for ProMate Sea Viewer Scuba Dive Mask (MK270.) Optical lenses available from -1.0 to -10.0 by increments of 0.5 (for near sighted). Optical lenses available from +1.0 to +4.0 by increments of 0.5 (for far sighted).