This Citizen men's wristwatch is a sports watch despite being fitted with a black leather strap, with a black background dial and a steel case with domed mineral glass. Eco-Drive technology is designed to convert both natural and artificial light into energy for the operation of watches. Eco-Drive watches do not require battery replacement or, in the case of mechanical movements, periodic reloads to maintain constant operation. Eco-Drive technology is designed in such a way that any light source, regardless of its intensity, generates the energy necessary for the watch to function. One of the distinctive features of Citizen Eco-Drive compared to other technologies for the continuous operation of the watch is its "power reserve". Eco-Drive watches, when fully charged, continue to run for more than 6 months, even in complete darkness. The radio control system installed on the clock receives the time signal generated by an atomic clock and transmitted by means of radio waves. The accuracy of the atomic clock and of each radio controlled Citizen clock is absolute, with a tolerance of 1 sec every 10 million years.