This Omega Ref. CK 987 chronograph was introduced in the late 1930s as part of Omega’s transition into wrist‑worn chronographs powered by the robust Caliber 33.3, developed by Lemania and first adopted by Omega in 1933 and can be considered the direct predecessor to the later Caliber 321. The 37.5 mm stainless‑steel case, measured excluding the crown, is a size relatively large for its era. The case shows only light signs of wear and shows the correct hallmarking and serial numbers. The snap‑on caseback closes firmly, and the plexiglass is in an excellent condition. The watch is fitted with a  silvered service dial, with raised Arabic numerals, and the classic sub‑registers for seconds and 30‑minute chronograph count. The dial is in an excellent condition, it shows only some very small blemishes and it is very sharp with no oxidations. Inside, the Omega Caliber 33.3 T3 manual‑winding chronograph movement is in a good working order. Revered as one of Omega’s most early chronograph movements, it combines technical merit with a historical footprint in Swiss horology, being based on a Lemania 15 caliber, one of the cornerstone among vintage chronograph movements, which remained in production into the early 1950s. This chronograph is fitted with a vintage‑style leather strap, it has been fully serviced in‑house and is delivered in a good working condition, Accompanied by our six‑month guarantee and certificate of originality, Worldwide shipping is available. Please contact us for further information or purchase arrangements.