A hand mine is an explosive device used for demolition work, capable of being detonated automatically or placed on a timer.
Thane is in possession of a hand mine during his attack Vickers aboard shuttle UIY 1138, paralyzing him in the process by a knockout capsule (TOS: "The Gun on Ice Planet Zero, Part I").
When captured by a Cylon patrol in the Theta's city on Arcta, Thane pawns 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 a small contingent of the Centurion detachment before an assemblage of Thetas (TOS: "The Gun on Ice Planet Zero, Part II").