Monkey Wrench (5e Equipment)
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Simple Melee Weapons
It's a big wrench that is both good at repairs and bashing heads in.
Special. If you are proficient with it, the monkey wrench by itself counts as a full set of tinker's tools. You also use the monkey wrench repairing damaged constructs or objects if you are proficient with it; Each hour spent repairing a construct or object restores 1d4 + 3 hit points to it.