Gehmann #510 Rearsight Adjustable Iris 0.5 - 3.0mm

Gehmann #510  Basic Iris

shorter still and adjusts over the wider range 0.5 - 3.0 mm
the fixed seat iris works with individually pin-located tempered spring steel leaves
aim point precisely maintained throughout the wider range of adjustment by introducing a new system of aperture control operated by varying the pressure of a steel tube against the central aim point - guaranteeing a perfect circle
light reflection kept to a minimum by use of matt finishes internally and externally
unique Gehmann patent not found in other irises
Thread is male M9.5