Can be portable, made of strong laminated plastic. Some yellowing due to age. The scoring is 6/x where the x is the number below the smallest line of letters correctly read. If the patient reads bottom line “4” at 6m the VA is 6/4. The following lines when tested at 6m: 6/24, 6/18, 6/12, 6/9, 6/7.5, 6/6, 6/5, 6/4. The binding is completely secure but is in 3 pieces.
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