Clock gearbox

Clock with 1:12 reduction gear set, and option to drive the minutes shaft via its exposed, extra 28 teeth / 1.5mm module gear.

Shaft for hour hand is 6 mm in diameter.
Shaft for minute hand is 3.5 mm in diameter.
Hollow shaft thread of lid has M10 thread.

Screw holes are for self-tapping screws with outer thread diameter of 2.6 mm.