The Seiko Crystal 305V06GNS is a genuine Grand Seiko crystal specifically designed for the 6106-8630/8640 models, as well as the 6155-8000 and 6156-8000. Made in Japan, this high-quality crystal is a perfect fit for those looking to replace or upgrade their watch with authentic Seiko parts. With the Seiko brand reputation for excellence and precision, this crystal ensures a perfect fit and reliable performance for your timepiece.