A blasting machine or shot exploder (commonly called a plunger[citation needed]) is a portable source of electric current to reliably fire a blasting cap to trigger a main explosive charge. It is mostly used in mining and demolition.
The use of the term "machine" dates from early designs that used an electrical generator operated by winding a rotary handle or pushing down a T-handle. Modern blasting machines are battery-powered and operated by key switches and push-buttons, and do not resemble the older designs.