The Diver 300M in brief
Every reference starting with 210 is a current Seamaster Diver 300M, and this one is 42 mm across, the size of most Diver 300M models in the shop. The 20 in the fourth group is Omega’s code for a self-winding watch without a chronograph, so there are no pushers on the case.
Bezel and crown
The bezel rotates, so you can set its marker against the minute hand and read how long you have been in the water. The crown screws down to close the case: open it to wind or set the time, and screw it back in before the watch gets wet.
Timekeeping
Our movement guide gives our automatics about +4 to +8 seconds a day and 50-60 hours of power reserve. Those are general figures, not a promise for one watch; if you want a reading for yours, ask for a timegrapher result together with the QC photos.
Size and weight
Our size guide puts a 42 mm Diver 300M in the range for wrists of 16.5 to 19 cm and gives about 178 g on the bracelet or about 125 g on rubber. For a side-by-side look, the Diver 300M 210.30.42.20.01.001 shares the size, and our Diver 300M guide has more on the model.
Shipping
You get photos and a clip of your actual watch to approve, then it goes out in a plain parcel with no brand names on it. The Omega presentation box is sold on its own.
















