1978 Tudor Chronograph Big Block (Ref. 9420/0) Black "Solo Dial"

The early Tudor Chronograph references do share a lot of common traits with the big brother Rolex Daytona references including the same steel bezel with engraved tachymeter scale, Rolex Oyster bracelet, as well as the Rolex Trip-Lock crown and screw-down pushers. The dials of these Tudors also reference the Rolex Daytona's of this era as they possess the same trapezoidal applied markers and either silver or black dials, although some Tudors did feature some more unique and colorful dials over the years. One aspect that does set the two chronographs apart, however, is the movement. The Big Blocks utilize the workhorse Valjoux 7750 movement, which is both self-winding and features a quickset date function, great for quickly switching the date.

"Solo Dial" is in reference to the dial text, or lack thereof. Underneath "Tudor", where you would normally find the text "OYSTERDATE" there is simply nothing. This from factory dial characteristic, recognized as the first dial execution of the 9420/0 is extremely rare. Uncommonly seen, but known, Rolex "Solo Dial" chronographs are often only seen and sold through high-end auctions. Being that there are only a few known Tudor 9420/0 Big Block "solo dials" that exist, makes this specific piece a highly coveted example within the collector community. 

Stock # TBBC94200SOLO
Brand Tudor
Style Big Block Chrono 
Model 9420/0
Serial 88XXXX
Size Men's
Material SS
Millimeters 40
Bracelet Rolex 78360 Oyster Bracelet W/ 589 End Pieces



The wonderful case was previously polished and shows honest signs of use, and retains full and even lugs. The black acrylic "UPH" bezel is in exceptional condition, showing minimal signs of use with no cracking or delamination. The case retains its original screw-down pushers and "Rolex" signed trip-lock crown. The Rolex 78360 Oyster bracelet features the correct 589 end pieces and exhibits very little stretch from and retains 11 links.


The rare matte black "solo" dial with silver sub-dials is in remarkable condition, showing no blemishes. The sub-dials remain in very clean condition and have aged to an impressive champagne patina which give the watch a unique and cool vintage aesthetic. The tritium lume plots have aged to a charming creamy patina, under U.V. light inspection there is degradation in the 1, 6, and 9 o'clock lume plots, the rest of the lume plots remain fully intact. The original tritium hand match the dial nicely and show no degradation when inspected under U.V. light.


None. The watch is functioning perfectly and keeping time, previous service history is unknown.