A choice of two quartz-controlled clock movements, accurate to within ±30 seconds per month and capable of running for one year on a single AA battery 309018 (not supplied). The body is 55mm square and 15mm deep and there is a choice of shaft protrusion beyond the front face of the case of either 14.5mm or 23.5mm. Thread lengths are 7mm and 16mm, your choice dependent on the thickness of the dial being used. A hanger plate is provided with each movement.