Most of today's quartz clocks, which are actually regulated by a man-made crystal, oscillate at approximately 32 kHz when electrically charged. This vibration in the crystal in turn creates electric impulses at the same rate, which are then electronically divided into longer pulses. Usually these pulses are transferred to the second hand at 1-second intervals, creating the tick-tick sound we normally hear. Because a ticking sound can be a nuisance for some — especially if the movement is mounted in a clock case that has good acoustic value — these continuous sweep movements were developed to pulse 16 times per second. This makes the second hand move in a manner that is seemingly uninterrupted and virtually silent.
These compact single AA battery-operated quartz movements are available in a choice of three shaft lengths — 1/8", 1/4" or 3/8". The shaft length is the threaded portion that will fix onto the dial plate or piece of wood. Choose the shaft length based on the thickness of material to be used. All shaft diameters are 5/16". The dimensions are 2 7/32" × 2 7/32" × 5/8". Batteries not included.