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