Seiko Case Back Gasket Seal replaces. I have collected Seiko watches for 50 years. For sale, 1 Flat Gasket Seal Ring (0.5 mm thick). I can check you have the correct part, or give you the correct part number.
The Seiko Case Back Gasket FE298BAD2/7S26 & 7s36 product would be ideal for restoring and maintaining vintage or high-end mechanical watches.