550 Gehmann rearsight iris with twin polarisers

Incorporates the patented 510 iris
Adjustable over a wider range of 0.5 - 3.0mm
Two polarisation filters:
- 1. ring eliminates reflections and controls white around target
- 2. ring (with stainless lugs) controls light through the sight and enables varying degress of brightness
10 - 90 % light absorption via the twin polarisers
Can be used as an iris only - or with one, or both, polarisers
Removable steel threaded connection which enables the use of a diopter
Easy clean instructions are included