RARE WWII Mortar Sight Lensatic MKI

This is a rare WWII Sight Lensatic MKI for 3 and 4.2 inch Mortars. It was used by both British and US forces during WWII. It was designed to measure bearing and angles and would be attached near the muzzle end or was mounted on one of the mortar's legs. The makers mark looks to be LOC. It has two sets of numbers both of which look to British as does the drab olive paint. Interestingly it shares some similar features and parts found on the Vickers machine gun dial sight.