Abstract: A metal detonator housing has a central opening extending therethrough between upper and lower ends and a detonator located in the opening at the lower end. Two leads are conencted to the detonator for causing the detonator to explode upon the application of electrical energy to the two leads. A metal contact spring is located in the opening of the housing at the upper end and extends out of the upper end. The contact spring is electrically insulated from the housing. A spring is located in the opening of the housing and is coupled to the detonator for urging the detonator toward the lower end. One electrical leads extends from the detonator through the central opening of the housing and is electrically connected to the contact spring. The other electrical lead is electrically coupled to the housing.A shunting wire is provided with means for removably attaching one end of the shunting wire to the outside of the housing with the other end of the shunting wire being removably connected to the contact spring.