Grand seiko spring drive divers 9r sbga231 this classic grand seiko divers watch features the grand seiko unique spring drive movement caliber infamous for itsoutstanding accuracy of 1 seconds per day and approximately 72 hours power reserve the watch case and bracelet are made with high intensity titanium providing a durable scratch resistant finish and a substantialweight reduction perfect for those looking for a comfortable divers watch all of these characteristics arenotorious with