Switch No.9,Mk.I ' L Delay '.

An excellent example of a British Switch No.9,Mk.I ' L Delay '. This particular example produced a 6 hour delay. Developed by Millis Jefferis of MD1 the L Delay instead of relying on the chemical action of a corrosive liquid on metal (which was subject to temperature variation), it used a piece of metal under stress - the metal in question being a lead alloy that was extremely affected by mechanical creep. A piece of this lead was notched to a set diameter, the diameter setting the time delay. When the starting pin was removed, this wire was placed under tension by the spring-loaded striker, and began to gradually stretch. After certain time it would snap at the notch and allow the striker to hit the percussion cap. Generally speaking L-delays were slightly less reliablecitation needed and had shorter delays, but were more reliable underwater (if a No. 10 fuze developed a leak, water would dilute the corrosive liquid and increase the delay or stop the fuze from working). This example in excellent condition with remains of designations and batch numbers stencilled to body and engraved ' INERT ', complete with rubber snout shroud.
AVAILABLE in the UK ONLY
INERT.

Code: 9324