Hi Ian

yes it has the ridge but not right up to the fast focus ring , from the end of the scope to the ridge is about 22mm.

Rain stopped play last night as regards actually getting out with the NV , but i am happy that the Merlin is mounted very securely so not considered taking the stanley knife to the adapter rings yet!

The IR is connected via 3 chunky "pins" , which push fit very snuggly into the body of the scope. I really like this addition and the illuminated dot ret has already paid dividends when shooting squirrels/pigeons in trees

Cheers
Simon.