Sinn watch 917 gr the rally leather sinns 917 rallye chronograph is designed to be exceptionally functional and easy to use a dehumidifying capsule protects the dial from fogging one of the timepieces most useful features is the countdown bezel that is exceptionally easy to set additional functionalities include a power reserve indicator a date window at 4 o clock high and low pressure resistance transparent case back and scratch resistant sapphire crystal glass with anti reflective coat