Thermal
Detonator

The Thermal Detonator
is a horrible weapon. Once widely used in combat, the dirty looking
war weary weapon is said (fictionally remember, and among fans) to produce
an explosive effect like that of a small thermal nuclear explosion.
Pull back the hammer on it's top, which initiates it's arming sequence
and the thermal detonator is armed. All that's left is presumably push
the glowing red button.