The Nixie Watch goes beyond LED wristwatches by using old fashioned tubes to display time.The two Nixie tubes used in the Nixie watch are the widely available B-5870 type and are socketed for easy replacement in case of damage. The watch even has a programming adapter allows the GPL'd PIC firmware running the watch to be hacked. The case is made of lightweight aircraft aluminum. The size is 2.2" (55mm) diameter and it is 0.79" (20mm) thick. The battery life is approximately 4 months at 50 viewings per day, no seconds display.