This authentic Omega Planet Ocean Chronograph 45.5mm black rubber watch strap (part number 98000363) will fit Omega Planet Ocean 45.5mm Chronograph models with Calibre 9300 movements. It is 22mm wide at the watch end and tapers down to 20mm at the buckle end.
This strap is in good used condition and I have given you clear images of the strap from multiple angles to help you see the quality before ordering.
If you are not sure if this will fit your watch or if you have any other questions, feel free to email me at Sales@TheWatchLink.co.uk. I'm happy to help!