My SkyWatcher Wave 100i mount did not come with a holder for the hand controller. This model addresses that shortcoming. It is sized to fit the 40mm diameter legs of the SkyWatcher carbon tripod, but I have included the Fusion 360 file so changes can be made.

The holder itself leaves plenty of space around the hand controller, so foam or felt pads can be added for padding. I just used an off-cut of some 3M furniture felt.

Mounting is with four M3 or M4 bolts, slightly fiddly but works fine. It mounts very securely and doesn't slip or rotate.

The battery holder fits in the spare Losmandy mount. It fits a common 12V battery sold online. Tightening the clamp also tightens the battery holder. This also provides a secure fit.

The holder files are, somehow, not rotated correctly for printing - they should be placed vertically for optimal printing. I used PETG, which is sufficiently strong yet flexible for this application.