A-type detonator
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A-type detonators are used as a fuse. A-type detonators detonate an explosive, such as G-4, by means of an electric spark to incite a chemical reaction. They can be time-delayed or manually invoked.
Typically, A-type detonators are kept in cases of 12 with slots labeled A-1 through A-12; they are in small arms lockers onboard a battlestar. (Water)