Using your Shinola 40mm Automatic Bronze Monster GMT Watch is easy. The fourth hand rotates once every 24 hours, so just check it against the bezel marks to track time in different time zones. You can swap the black #tide® ocean - bound plastic woven strap with the deep brown leather strap whenever you want. For maintenance, keep it away from extreme temperatures and magnetic fields. Since it's rated at 10 ATM, it can handle normal water activities, but don't take it for deep - sea diving. Wipe it with a soft cloth regularly to keep it looking great. As the bronze case ages, it'll develop a unique patina, which is a natural and beautiful process.