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A hand mine is a type of explosive device used for demolition work. It can be detonated manually or placed on a timer.
When captured by a Cylon patrol in the Theta's city on Arcta, Thane pawnes off a hand mine as a tape coder with information pertaining to the rag-tag fleet. When a Centurion goes to use it, the Cylon kills Thane and destroys the Centurion detachment (TOS: "The Gun on Ice Planet Zero, Part II").