The 42mm Cover Ring Adapter from Pulsar is made to mount the Forward DFA75 night vision attachment to a daytime scope with objective lens diameters between 47 and 50mm. There are four inserts that will fit a majority of optical bells.
The adapter features a flip-up cover that replaces the scope's stock lens cover. The cover locks closed and has tabs to make opening it easy. The hinge is spring-loaded to flip the cover up and hold it in-place against the ring adapter so it won't obstruct the user's view over the top of the optic.
To attach the DFA75, remove the lens cover and slide the DFA75 into the bayonet mount and lock it into place. The cover ring adapter should be used with only one of the supplied inserts.