Tuning wrench

[1] Some early keyboard instruments have oblong-shaped tuning pins.

The tuner flicks the lever with his or her wrist, causing the weight to do the actual work of moving the tuning pin.

Tuning wrench sockets are often attached snugly to the handle with fine-gauge machine-screw threads, to provide a very firm, immobile joint; this is in contrast to the square snap-on joints found in sockets used for machinery.

This enables a better feel and control of the tiny movements of the tuning pin, within the pin-block.

T-shaped handles are used for many lower-tension instruments such as the harpsichord, harp, and dulcimer.