This ROLEX watch is commonly referred to as the “Dress Explorer" versus the steel tool watch or sports Explorer as they have a gold bezel and gold winding crown.
The reference 5501 stainless steel ROLEX OYSTER case dates the watch to 1958. As many know the reference 5500 (steel) and 5501 (gold bezel and crown, two-tone) also appear in the ROLEX AIR-KING line of watches from the same era. The EXPLORER versions are much rarer of the two types. The case on this EXPLORER measures 34mm. and houses a butterfly caliber 1530 or 1560 rotor depending on the ages, automatic winding super precision movement. The original raised gold markers and original Dauphine hands with steel sweep second.
My preference for Explorer has always been for the sport model black dial with the 3,6,9 markers. Previously, I will not take a second look on the Dress watch explorer owing to my own prejudices. However, I have come across this rare CANADIAN version ROLEX EXPLORER PRECISION dating to 1958 that captured my attention owing to its black dial and raised 3,6,9 markers as well as the fact that it is a gilt dial plus having the old 1530 butterfly rotor. Recently, I have moved to explore the various diver watches and it's a good feeling to come back to the good old Rolex. This 5501 Explorer will fit in nicely with my other 5500, 1016, 6610, 1655 and 16550. Missing in the pack is the 5504 Explorer I guess...
There are two types of 1530 movements with the earlier butterfly movement being more desirable.