During World war II, many countries developed a series of “switches” and “demolition firing devices” for use by their military forces and partisan resistance operatives and agents.

They were arsenal-made, robust, and reliable, and their main use was for sabotage behind enemy lines. Reports from the field often led to improvements, and slight changes to make the device more reliable or adaptable to multiple types of operations as the war progressed.

Many of the original ones were developed in England, and were copied by the United States, who then went on to develop their own. They operated on a variety of mechanical and chemical principles.

The devices were fitted with several different couplers or threaded adaptors, allowing them to be attached --with detonators --into fuze wells of mines, hand grenades, demolition blocks, mortar rounds and artillery projectiles.

Many of these devices have in turn since been copied by other countries, and newer designs have also been added.

The Australian Multi-Purpose firing device was made for many years under licence by the US Government.

We offer cast and machined replicas of many of these devices, along with cutaway images of internal their mechanical arrangements and detailed descriptions of how they work.

Many of the military items are based on the same operating principles as the improvised types. Together, both types provide the instructor with an excellent overview of boobytrapping principles and hazards presented in trying to defeat them.