| Type | Thin-crack jam |
| Crack size | Finger-width |
| Locks by | Slotting + torquing fingers |
| Difficulty | Intermediate |
A finger lock is a crack-climbing technique where you slot your fingers into a thin crack and twist or torque them so they lock against the walls. Used in cracks too narrow for a hand jam, finger locks can feel surprisingly secure once trusted, but are strenuous on the fingers and take practice to use well.
How it works
Slide fingers (often thumb-down) into a constriction, then torque so they cam against the crack — using the pinch plus twist rather than expanding the hand.
Finger lock vs hand jam
Finger locks suit finger-width cracks; hand jams suit hand-width ones. See finger lock vs hand jam and crack climbing.
Frequently asked questions
What is a finger lock?
A finger lock is a jam for thin cracks: you slide your fingers in — often thumb-down — to a spot where the crack pinches, then twist so the fingers cam and lock against the walls. It uses the crack's constriction plus torque rather than expanding the whole hand.
What's the difference between a finger lock and a hand jam?
A finger lock is for finger-width cracks and works by torquing the fingers, while a hand jam is for hand-width cracks and works by expanding the whole hand. Finger cracks generally feel more strenuous and precise than comfortable hand cracks.
Do finger locks hurt?
They can be uncomfortable and hard on the finger tendons, since they load the fingers in a torqued position. Building up gradually, finding the best constrictions, and not over-gripping help reduce strain while you learn to trust them.
Sources
- Crack climbing technique — American Alpine Club