The casio -shock gravitymaster men’s watch is designed for the adventurous spirit, combining durability and style. Black dial 54. 0mm bio-based resin case with carbon fiber core; mineral crystal features include world time, timer, stopwatch, alarm, double led light, neobrite, and calendar smartphone linking using bluetooth⮠powered by tough solar: battery rechargeable by light neon yellow bio-based resin strap; buckle clasp shock-resistant; water-resistant to 200 meters we are an authorized casio dealer