The rotary pen
A DC motor in a pen-shaped body turns a cam that drives a shaft up and down; a sterile disposable cartridge clicks on the end. The artist sets needle projection (how far the tip pokes out) with a twist of the grip and speed (strokes per minute) on a power unit or wireless module.
Pens are light, quiet, low-vibration and precise — ideal for the small, controlled movements lip work needs — and the fully enclosed cartridge with a membrane makes cross-contamination control straightforward.
Coil and 'digital' machines
Traditional coil tattoo machines (electromagnets snapping an armature) are powerful and give strong feedback but are heavy and buzzy; few cosmetic artists use them on lips. 1990s–2000s 'digital' micropigmentation devices with fixed handpieces are largely superseded by pens.
Actuation and hygiene
Whatever the machine, the needle must not be able to draw fluid back into the body of the device: cartridges have a rubber membrane, and machines used without cartridges need a barrier sleeve plus a clip-cord sleeve. Machine body, cord and power unit are wrapped for every client.
