Sinn watch 356 sa pilot ii glass front back leather apart from being exceptionally functional this 356 sa pilot ii instrument chronograph by sinn brags stylish and very elegant design the movement has a 42 hour power reserve it is protected from shock and magnetic fields a day and date window is positioned at the 3 o clock mark additional functionalities include electroplated and uv resistant dial transparent case back and scratch resistant sapphire crystal glass with anti reflective coat