A video showing you how to quickly change the lens on a pair of Swans FO2 OP.
Use this method to make up a pair of goggles where different strength diopters are required in each eye.
In this example we take 1 pair of -2.5 and 1 pair of -4.0, and combine them to pake two pairs of -4.0/-2.5 in under 60 seconds.
It is worh noting each eye piece can be used as either a left hand side or right hand side.