For ignition, electric caps require one and one-half amperes of electricity passing through their wires. Nonelectric blasting caps. These caps may be initiated by time blasting fuse, firing device, and detonating cord. The M7 special nonelectric blasting caps are flared at the open end for easy insertion of the time fuse. Both caps are made to set off less sensitive military explosives.
Electric caps are RF sensitive and require lengthy firing wire.
Nonelectric caps are not to be used to prime charges placed underwater or in wet boreholes because they are difficult to waterproof. Replaced by MDI components for all demolition missions in the Army except in the SOF, and EOD communities.