This is my first 6309 diver series and it keep great time for it's age.
CASE: Original, polished
BACK CASE: Original
CRYSTAL: Aftermarket dome crystal
BEZEL INSERT: Aftermarket Pepsi style
FUNCTION: Time, Day & Date.
MOVEMENT: Original Seiko 6309 Japan Automatic Movement, 17 Jewels
Love this model as it is really comfortable in my hand, almost similar to 'Sumo' in size.