Seiko Spring Drive Spacewalk – specially designed and built to accompany the first private individual to conduct a spacewalk. Seiko wanted to become involved with creating a space watch because of the technical challenges it presented.
The challenge for the Seiko engineers was to create a space watch that would be able to have accurate timekeeping, be reliable and comfortable and also withstand the harsh environments of not only space flight but also a space walk.
Seiko decided to use a spring drive movement since its less affected by extreme temperatures due to its Tri-synchro Regulator as opposed to a traditional regulator.
The mechanism provides the following functions: hours, minutes and seconds, calendar, GMT , 72-hour power reserve, and 12-hour chronograph.