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Slipjoints tend to be smaller than other typical pocket knives.
An electrician's knife typically has a locking screwdriver blade but a non-locking knife blade.
In Spain, one early lock-blade design was the Andalusian clasp knife popularly referred to as the navaja.
Opinel knives use a twist lock, consisting of a metal ferrule or barrel ring that is rotated to lock the blade either open or closed.
It is designed to be carried in the wallet along with regular credit cards.
Some credit card knives can contain other small tools, such as tweezers, or toothpicks.