Mole Grips
AKA: Locking Grips, Locking Pliers, Vice Grips
Mole grips can pinch fingers and lock in place, causing nasty wounds. Be careful when adjusting and always use hand protection.
Given their entirely metal construction and lack of insulation, do not use mole grips on live wiring, as the risk of electrocution is extremely high.
An adjustable and lockable tool for gripping things.
Mole grips in locked position with jaws at medium setting.
To use, open the jaws by unscrewing the bolt at the bottom of the handle, then close the grips around the item you want to grip and tighten the bolt again, until you can't tighten it any more. Then squeeze the lever on the other side against its handle to release the grips, tighten the bolt a little more, and grip the item again. Repeat as necessary, adjusting the grips for your situation.
You may find this tool useful for holding moderately heavy materials like wood and thin metal in position, while you weld or glue them. They can also be useful for holding a bolt while tightening a nut with the other hand.