CasebackHow it's worn

How it's worn

Under the caseback

The disc sits on the back of the watch, between the watch and the wrist. The whole face that touches the caseback is a microsuction pad: it is designed to hold without glue and without magnets near the movement, and to come off and go back on.

It is designed at 25 mm across and 3.1 mm thick, with a rounded edge on the skin side. From the outside the watch looks the same.

Charged on its base

The disc clicks into the charging base skin face down. A hook and a sprung latch go into two pockets in its rim and hold it down on two spring pins, which touch the two steel contacts on that face.

A button on the rim of the base lets it out. The base takes USB-C and has no magnet. The disc does not have to come off the watch to charge: the watch lies dial up on the base and the disc clicks in the same way, and so it does in the band.

Without a watch, in the band

For sleep or training without a watch, the disc goes into a band: a woven strap that starts in a silicone holder, goes once round the wrist, passes through a steel buckle and closes on itself with hook-and-loop.

The disc goes into the holder from the skin side and its face stays out, so it charges without leaving the band: the charger clicks on the same way.