I just want to update on the actual dimensions of the Invicta Pro Diver 8926c/ob crystal. I own three Invicta Pro Divers of various styles but with identical case sizes (40mm) and have upgraded them all to sapphire crystals. If you've happened to damage your crystal or just want to upgrade to a scratch-proof sapphire, the perfect size to use would be a 30.5mm (diameter) x 2.5mm (thick) flat crystal. Then you should be able to reuse your original gasket and just press the crystal in using a case press (if you don't have one, you can tape up the bezel and use a flat block of wood to carefully push it in). On my first replacement, I've used a 2.0mm thick crystal and it worked fine; however, I'd used a 2.5mm crystal on my second watch and found it had a better height (protrudes a bit better and makes the watch look more solid). If you've scratched up your bezel from daily wear and tear, you can get an aftermarket Rolex Submariner bezel insert of any color from Ebay and swap it in (the best time to replace the bezel is when the crystal is off). In the pics attached, I've installed a dark green bezel insert to replicate the look of the Submariner LV 50th anniversary edition. Enjoy.