Sea Ranger II
1966–1970 · 10k Rolled Gold Plate / Stainless Steel · Manual Wind
About the Sea Ranger II
Made from 1966 through 1970, the Sea Ranger II runs on Hamilton's caliber 688, a 17-jewel manual wind movement housed in a 10K yellow RGP and stainless steel case. The watch was part of Hamilton's broader marine-themed lineup of the mid-to-late 1960s, a family that includes the Sea Crest III, the Seaman, and the Seaman II, among others. Hamilton marketed it with waterproof and dustproof claims alongside shock resistance and an unbreakable mainspring, positioning it as a practical, durable everyday watch at an accessible price point.
Finding a Sea Ranger II in solid shape is reasonable but not trivial. The Gold Filled bezel area on RGP cases can show wear through to the base metal if the watch saw regular use, so checking the case edges and high-contact points matters. Two dial configurations appear on these: an all-numeral dial and a textured dial variant, and the 1966 catalog also references a silver dial with stick markers, so some variation across the production run is genuine and worth paying attention to when comparing examples.
From the Catalog
Hamilton's 1966 catalog listed the Sea Ranger II at $59.95 on bracelet and $49.95 on strap, describing it as a 10K yellow gold-filled case on stainless steel back. Hamilton emphasized its practical credentials in period advertising: 17 jewels, shock resistance, anti-magnetic construction, an unbreakable mainspring, and waterproof and dustproof protection with seals intact.
Hamilton Catalog Images
1960
1966
1968
What to Look For
| Dial | Check for moisture damage, which shows up as spotting, discoloration, or separation near the numeral markers. The embossed gold numerals can develop patina or show wear if the crystal was ever compromised. Compare the dial style against the known variants: all-numeral and textured both exist, so make sure what you're looking at matches what you're being sold. |
| Crystal | These came with a mineral glass crystal. Look for deep scratches or chips around the edges, and check the seal between the crystal and case, since any gap there means the dustproof rating is gone and the dial has been exposed. |
| Movement | Oil dries and congeals in any movement of this age. The caliber 688 is a manual wind, which means there's no rotor adding wear, but a service-deprived example will run erratically or stop entirely. Ask when it was last serviced, and if the answer is unknown or vague, budget for a cleaning and oiling before trusting it. |
| Case | The 10K yellow RGP layer is thin by design, and years of wear will cut through it at the lugs, crown shoulder, and case back edge. Look carefully at those spots in good light. Minor wear is normal and honest; heavy wear through to bare metal changes the value conversation. |
| Crown | The crown on the caliber 688 can detach from the stem if pulled too hard, and replacements that match the original profile are not always easy to find. Check that the crown is original, seats flush against the case, and winds smoothly without excessive resistance or wobble. |
The Movement
The caliber 688 is a 17-jewel manual wind movement made by Hamilton during the 1960s. It winds from the crown, has no date complication, and keeps time with a sweep seconds hand. It's a straightforward, serviceable movement with no exotic complications to worry about, which makes it practical for a watchmaker to work on and a reasonable choice for a daily wearer once properly cleaned and oiled.