Why This Watch Matters An extremely handsome example of a classic Super Compressor dive watch from Hamilton, this technical timepiece from the 1970s looks great in or out of water. The Full Story The two cross-hatched crowns are a sign of the famous Super Compressor case, which was patented and manufactured by the supplier Piquerez. Those cases relied on a very ingenious principle: they were constructed so that as water pressure on the outside of the case increased, the gaskets would be further compressed so that the watch actually became more water resistant the deeper you went. For that reason, the crowns are not even screw-down (as you will find, by contrast, in the Oyster case from Rolex, among others). The Super Compressor cases came in two sizes: 42mm, as seen in vintage Longines Divers, or 36mm, as seen in this Hamilton 600. This watch is extremely comfortable on the wrist with none of the design eccentricities or stylistic exaggeration that detract from so many timepieces from the 1970s. It’s aged very well with even, rich patina on the hands and lume plots. Overall, this is a terrific example of how function and aesthetics can be on an equal playing field in watchmaking. The Fine Print Maker: Hamilton Model: Super Compressor 600 Reference: 64040-3 Year: 1970s Case No: NA Material: Stainless Steel Dimensions: 36mm diameter; 12mm thickness Sapphire Crystal: No Lume: Yes, tritium Caliber: Automatic movement Hamilton 64A Bracelet/Strap: HODINKEE Aged Moss Green Leather Strap Lug Width: 18mm Box/Papers: No What we Love and What You Should Know The Super Compressor case is in great condition, of course coming with the two original cross-hatched crowns. The dial and inner bezel do not display any flaws. The lume is consistent between the hands and indexes; however, note that there are some sparsely distributed, minor dark spots on the metallic bases of the indexes. The watch comes on a brand new HODINKEE strap.