English: Small copper alloy medieval rotary key. The key has a simple circular bow and a sub-circular sectioned shank. The bit is a plain flat rectangle and there is a small perforation in the end of the shank. This simple form of key was long lasting from at least the late 12th – late 14th century and it has been suggested that they were used for caskets. Some similar examples can be seen in Egans, Medieval household, Fig.86.