Set and forget wall clock accurate to one second in 138 million yearsadjusts automatically for gmtbstradio controlled25 cm diametershortcode tabdescriptionthis attractive radio controlled wall clock from watchmakers tavistock jones is incredibly precise it is radio controlled from the uks atomic time regulator being accurate to one second in 138 000 000 years and adjusts automatically for gmtbst stylishly modern with a bold easy to read face its powered by 1xaa battery included a