INERT DEACTIVATED. RARE, WW2, SOE & Reserve Units Switch, No. 9, "L" Delay, Mk. I Time Pencil in Original Tin. Sn 23569:3 INERT DEACTIVATED. RARE, WW2, SOE & Reserve Units Switch, No. 9, "L" Delay, Mk. I Time Pencil in Original Tin. Sn 23569:3 Various Other Ammunition

This delay switch was developed by MD1 in February 1940 and was in full production from October of 1940. It is based on the fact that Tellurium lead under load, will stretch uniformly and eventually break. The switch is housed in a tubular body made either of brass or steel. The lead rod is turned down to form a small dumbbell shaped element that is then pegged at its upper end into a brass collar. An adapter or spring clip with percussion cap or 1.7 grain detonator is crimped into the extreme bottom of the body tube. The starting pin fits through the body and striker collar preventing movement of the collar and thus relieves any tension being put on the lead element. A small clip on the end of the starting pin prevents it from falling out accidentally. A small plastic tab on the starting pin gives the delay time of the switch. When the starting pin is removed, tension is transferred to the lead element. The lead begins to stretch and will eventually break releasing the striker to hit the cap to ignite a fuse or fire the detonator. The switches were issued with a number of different delays. The delay times were varied by the diameter of the centre portion of the lead element. Delays were 1, 6, 12 and 24 hours and 3, 7, 14, and 28 days, measured at a temperature of 65 degrees. This is an original WW2 time pencil with the original copper safety pin. The pencil is contained in an original black japanned with green paint round the middle, 2 piece tin plated container which originally contained 5 time fuzes. The price includes UK delivery and no licence is required to possess as part of a collection or display. Sn 23569:3