F2 Finger Camera with Action Mount

Small enough to grip between two fingers, which is the whole idea: it records what you are looking at rather than what a tripod is pointing at. The quick-release foot is the standard action-camera pattern, so it takes the helmet, handlebar and chest mounts you already own.

Footage goes to a TF card and charging is over USB-C. The box shows it on a helmet, a bike, a hiking pole, skis and a kayak, which is a fair summary of what it is for.