PD Meter (pupilometr) CT4107 "Thunderbird"

Specifications:
• Method of measurement: cornea reflection light coincidence method
• Range of measurement: 44 to 83mm (both eyes)
• Graduations: 22 to 41.5mm (each eyes) 0.5mm
• Range of focusing point: 30 to infinity
• Power supply: 6V DC (Lr03 batteries X4)