here's one you don't come across very often, a No.210 time fuze with the contour of a 117/119 impact fuze allowing quick change from impact to air burst fuzing without the need to recalibrate. This is an early one, batch 30 dated 1939 - they weren't introduced to service until 1940. Runs on a 60 second Swiss Tavaro clock. Shown next to a No.209 of similar manufacture.