It's extra rugged design makes this men's casio rangeman digital watch an exceptional timepiece. Digital display 53. 2mm black bio-based resin case - a plant-based renewable material - with mineral crystal solar-assisted charging optical sensor to measure heart rate compass, altitude/air pressure sensor, thermo sensor that measures temperature accelerometer and gyroscope to detect body movement black resin strap with buckle clasp shock resistant; water resistant to 200 meters we are an authorized casio dealer