Omega · Seamaster Diver 300M Chronograph · steel and Sedna gold · black · on Amazon
The two-tone Seamaster chronograph. 300 metres, Sedna gold, the 9900.
This is the Seamaster Diver 300M as a chronograph in two metals: reference 210.20.44.51.01.001, a 44mm steel case with an 18k Sedna gold bezel carrying a black ceramic ring, a black ceramic dial laser-engraved with waves, two counters, the date at six, Sedna gold crown and pushers, a helium valve at ten, on the steel and Sedna gold bracelet. Inside is Omega’s co-axial calibre 9900, a Master Chronometer automatic chronograph with a 60-hour reserve, tested by METAS; 300 metres. Listed under Omega’s own price when we read it, from a marketplace dealer.
Case
44mm, 17.20mm thick, 21mm lugs, 52.80mm lug to lug, steel with 18k Sedna gold bezel, crown and pushers, black ceramic bezel ring, helium valve, sapphire caseback, 300m, about 237 g
Omega 210.20.44.51.01.001; listing: 44mm
Movement
Omega co-axial calibre 9900, automatic column-wheel chronograph, Master Chronometer (METAS), 60 h
Omega; listing: Master Co-Axial chronometer
Dial
Black ceramic with laser-engraved waves, Sedna gold applied markers, two counters, date at 6
Listing: black dial; photograph; Omega
Bracelet
Steel and 18k Sedna gold, foldover clasp with diver extension
Photograph; Omega
Reference
210.20.44.51.01.001
Listing title and model row
Seller
Luxor Watches, marketplace dealer; in stock; 30-day returns; condition not stated
Amazon buy box, 2026-09-14
The 2018 Seamaster, as a chronograph
Omega rebuilt the Seamaster Diver 300M in 2018 with a ceramic bezel ring, a ceramic wave dial, a conical helium valve and Master Chronometer movements, and the chronograph version puts the calibre 9900 inside a 44mm case that keeps the full 300 metres. Steel and Sedna gold is the two-tone version: gold bezel, crown, pushers and bracelet centre links against black ceramic. It is a heavy watch at 237 grams on the bracelet, and it is the most watch in the Seamaster line short of the Planet Ocean.
The 9900 shows through a sapphire caseback; 15,000 gauss of magnetic resistance is part of the METAS test.
Reading the listing
The listing carries the reference 210.20.44.51.01.001 in the title and model row and calls it a Seamaster 300 Master Co-Axial chronograph with a black dial. The photograph shows the Sedna gold bezel and pushers, black ceramic bezel ring, wave dial and two-tone bracelet. The thickness, lug width, lug to lug, weight, calibre, METAS certification, reserve, 300 metres and list price are Omega’s published figures for the reference.
The dealer is Luxor Watches, a marketplace dealer, and the rows we read do not state whether the watch is new with Omega’s five-year warranty; ask, and ask for the box and card. Nothing here was measured on the watch.
Buying it on Amazon
This is a regular Amazon listing from a marketplace seller with Amazon’s 30-day return window; it is not a Luxury Stores pre-owned unit and the seller has not published a condition. The second button opens the live search for Seamaster chronographs in case this one has sold.
Seamasters have resold for under new and close to what pre-owned buyers paid, sometimes more, sometimes less; that is a pattern, not a promise, and nothing here is investment advice.
Specs
- Reference
- 210.20.44.51.01.001
- Case size
- 44mm, 17.20mm thick, 21mm lugs, 52.80mm lug to lug, about 237 g
- Case material
- Stainless steel with 18k Sedna gold bezel, crown and pushers; unidirectional bezel with black ceramic ring; helium escape valve; sapphire caseback
- Movement
- Omega co-axial calibre 9900, automatic column-wheel chronograph, Master Chronometer (METAS), 15,000 gauss
- Caliber type
- Omega 9900 co-axial Master Chronometer
- Crystal
- Domed sapphire, anti-reflective both sides
- Water resistance
- 300m (30 bar)
- Power reserve
- 60 hours
- Complications
- Chronograph (60 minutes and 12 hours on one counter at 3, small seconds at 9), date at 6
- Origin
- Swiss Made
Specifications as published by Omega. We research from manufacturer documentation and published sources rather than hands-on testing. Researched 2026-09-14.
Verdict
Omega’s Seamaster Diver 300M Chronograph in steel and Sedna gold with a black ceramic dial and the Master Chronometer 9900, on Amazon from a marketplace dealer under Omega’s list price.
Strengths
- 300 metres in a chronograph, with a helium valve
- Sedna gold bezel, crown, pushers and links against black ceramic
- Master Chronometer 9900, 60 hours, 15,000 gauss
- Listed under Omega’s own price when read
Trade-offs
- Condition and warranty card not stated by the dealer; ask
- 44mm, 17.2mm and 237 g; a heavy watch
- Two-tone is a commitment; the steel version exists
- The most expensive Omega on this page
Buy it if
Someone who wants the full-fat Seamaster chronograph in two-tone with Omega’s best certification.
Skip it if
You want all steel, a time-only Seamaster, or a stated condition.
FAQ
Omega’s co-axial automatic chronograph with Master Chronometer certification: column wheel, silicon balance spring, twin barrels for 60 hours, tested by METAS to 15,000 gauss, with the 60-minute and 12-hour counters on one sub-dial at 3.
Compare
OmegaSeamaster Diver 300M Chronograph 44mm 210.20.44.51.01.001 (steel and Sedna gold, black ceramic bezel, black dial, two-tone bracelet) vs Seamaster Planet Ocean 600M Chronograph 45.5mm 215.20.46.51.03.001 (steel and Sedna gold, blue ceramic bezel, blue dial, two-tone bracelet)
OmegaSeamaster Diver 300M Chronograph 44mm 210.20.44.51.01.001 (steel and Sedna gold, black ceramic bezel, black dial, two-tone bracelet) vs Seamaster Diver 300M Co-Axial Master Chronometer 42mm 210.60.42.20.99.001 (titanium, tantalum and Sedna gold, limited to 2,500)
OmegaSeamaster Diver 300M Chronograph 44mm 210.20.44.51.01.001 (steel and Sedna gold, black ceramic bezel, black dial, two-tone bracelet) vs Seamaster Diver 300M Co-Axial Master Chronometer 42mm 210.22.42.20.03.001 (steel and yellow gold, blue ceramic dial, blue rubber strap)Sources
- Omega Seamaster Diver 300M Chronograph 210.20.44.51.01.001, official page
- Amazon marketplace listing (Luxor Watches), read 2026-09-14
Researched and last updated 2026-09-14. We do not test watches in hand; every figure above is traceable to the manufacturer or the sources listed here.
Omega Seamaster Diver 300M Chronograph 44mm 210.20.44.51.01.001 (steel and Sedna gold, black ceramic bezel, black dial, two-tone bracelet)
Reference 210.20.44.51.01.001 · $10,000–$25,000
Prices and availability change; the band above is a research figure, so check the current listing.
Affiliate Disclosure
The Horologist is reader-supported. When you buy through links on our site, we may earn a commission at no extra cost to you. This never influences our editorial recommendations — every timepiece is selected on merit alone.
Complete the look
A fresh strap changes the whole watch.
Not ready today? Adding it to your cart keeps your pick saved.
Compared Against