In 1959, with the advent of reference 7928, TUDOR for the first time proposed the principle of guards to protect the winding crown from shocks. The variations in the execution of this protection were an illustration of the dynamic continuous evolution of the same reference, very characteristic of the first-generation TUDOR Submariners
Reference 7928, shown here and produced in 1959, presented the square version of these protections, called “Square Crown Guards” in collectors’ circles.
With these new protections, the size of the crown used would now be 6 mm. The case measured 39 mm in diameter, was waterproof to a depth of 200 metres and bore the signature “ORIGINAL OYSTER CASE BY ROLEX GENEVA”.
The design of its dial, hands and bezel was similar to that of references 7922, 7924 and 7925. Its movement was the self-winding calibre 390, just as for all the TUDOR Oyster Prince Submariners in the 7900 series.