SNAP ON LENSES TO FIT OPTI MASK MINUS
Negative dioptre lenses for those with near-sighted or myopic vision are available in:
-0.5 dioptre increments from -2.0 to -6.0.
Bifocal lenses for gauge reading and Camera screens are available in:
+0.5 dioptre increments from +1.5 to +3.5.