No22 Sight case (inner)

The No22C sight was the standard anti tank telescope untilo well after 1941, the September 1944 maintenence manual states that the No22 will be replaced in time by the No41, so for most of WW2 the No22C was in service. This case is the inner one, the sight was first placed in this and then into the outer case which was fastened behind the shield in front of the layer. The sight fitted into the sight holder via a removeable but left fixed adapter, presumeably designed to 'future proof' the sight mounting.