The SBS diver is possibly the quintessential CWC watch; whilst most other CWC watches and clocks have antecedents in other models, or have been made or supplied by other brands, only CWC has ever produced the black day-date dive watch for the British military. For this reason, as well as for the link to British Special Forces, issued versions of this watch are highly sought-after by collectors.
The watch was originally designed to the specifications of the Special Boat Service (SBS) in 1987; it has been suggested that special forces operatives wanted a non-reflective black metal finish for night time operations - possibly inspired by Royal Marines based in Hong Kong who had their issued RN dive watches black-coated locally - and that the day-date function was because they spent considerable amounts of time on mission and found it helpful to keep track of the days. The NSN 7995443 is specific to this watch.
The watch was first issued in 1988 with an acrylic bezel insert, similar to the Royal Navy dive watches of the 1980s. It was next issued in 1992 with a metal bezel insert with wide hashmarks (unique to the SBS and RN dive watches of that year), and then in following years with the standard, current metal bezel insert with narrow hash marks.
Known issue years and approximate batch sizes are as follows:
1988 - service code 0552 - approximately 100 watches issued
1992 - service code 0552 - approximately 150 watches issued
1993 - service code 0555 - approximately 100 watches issued
1994 - service code 0555 - approximately 300 watches issued
1997 - service code 0555 - approximately 200 watches issued
1999 - service code 0555 - approximately 100 watches issued
2000 - service code 0555 - approximately 50 watches issued
2001 - service code 0555 - approximately 500 watches issued
2005 - service code W10 - approximately 250 watches issued
In the early 2000s, the decision was made to make the SBS watch the "standard" issued dive watch and phase out the RN watch - which possibly accounts for the larger numbers ordered in 2001 and 2005.
The 2005 issued watch was requested by the Royal Engineers, and bears W10 service marks (for the British Army), with two different W10 markings seen. The lower numbers were supplied from a batch that had already been manufactured, with 0555 is struck out and W10 added; the higher numbers were manufactured with W10 on the case back. A few have also been seen with 0555 not struck out.
The 2001 and 2005 issued watches also had depth ratings on the back of the watches; in 2001 the text read PROFESSIONAL WATERPROTECTED 30 ATM / 990 FT; in 2005 the text read WATERRESISTANT 30 ATM, in two different styles - smaller font on the watches with 0555 struck out, and larger font on the W10 factory-marked watches.
The SBS is still supplied to the British military today, and is issued to units requiring a dive watch, including Royal Marines Commandos, Paras, Royal Engineer divers, and some supporting units of the Royal Navy. Supply recommenced in 2015, with further issues in 2017, 2018, 2019 and 2020. Watches supplied since 2017 have been the Mk II version of the watch with sapphire crystal and 120-click bezel.