This is my first Doxa sub300t watch. It's a pre Syncron Sharkhunter, with the sailboat on back. I own it for more than 40 years. I stored it for years after watch fell and the crystal snapped. Seven years ago I decided to restore it . I went for two or three watchmakers for an estimate but In the end I decided to do it on my own. Had to redial/Relume, find a new crystal, gaskets, hands, bezel spring and movement overhaul. Took me a while and finally finished it a few days ago. I'm very pleased to wear it again (though I'm not planning to dive with it)