Thinline 4007
1965–1967 · 10k Yellow Gold Filled · Manual Wind
About the Thinline 4007
The Thinline 4007 was produced from 1965 through 1967, part of Hamilton's Thinline family, which focused on slim American-made cases during a period when the industry was moving toward slimmer Swiss movements. This model runs on the caliber 687A, a 17-jewel manual wind movement, housed in a 10K yellow Gold Filled round case. The Thinline line is covered more thoroughly in the dedicated family guide, but the 4007 represents a clean, understated expression of that direction. Its appeal comes from the combination of minimal dial design and a genuinely slim profile.
The white dial version uses applied gold stick markers with no hour numerals, which gives it a spare, modern look that has held up well over sixty years. A yellow dial variant is also known to exist, with no seconds hand, so it's worth being clear about which version you're looking at before buying. Finding one in honest condition, with the original Gold Filled case still showing good surface quality rather than heavy wear through to base metal, is the real challenge with this model.
From the Catalog
Hamilton marketed the Thinline line in 1965 with an emphasis on its ultra-thin case design, 17-jewel movement, and practical durability features including shock resistance, anti-magnetic construction, and waterproof-dustproof protection when seals were intact. The 4007 was priced at $89.50, positioning it as an accessible but genuinely refined option within the Thinline lineup.
Hamilton Catalog Images
1966
What to Look For
| Dial | Check the white dial closely for spotting, discoloration near the edges, or any separation at the applied stick markers. The markers themselves should sit flush and even. If you're looking at the yellow dial variant, confirm the absence of a seconds hand, as that is characteristic of that version. |
| Crystal | The round case takes a flat acrylic crystal. Look for deep scratches or crazing, both of which are easy to miss at a glance but affect legibility. Replacement crystals are generally available, but confirm the fit is correct before purchase. |
| Movement | Ask about service history on the caliber 687A. Oil in a movement this age dries out completely and creates enough friction to stop it, often intermittently at first. A watch that runs fine during a quick test may start missing time or stopping altogether within days if it hasn't been serviced. |
| Case | The 10K yellow gold-filled case is susceptible to wear-through at the lugs and caseback edges over decades of use. Examine those areas closely under good light. Some wear is expected and acceptable, but worn-through spots exposing base metal significantly affect value. |
| Crown | Check that the crown winds and sets smoothly without slipping or grinding. On a manual wind movement, the crown takes regular use, so worn crown stems and stripped keyless works are not uncommon at this age. |
The Movement
The caliber 687A is a 17-jewel manual wind movement made in the United States, built around Hamilton's commitment to shock resistance and anti-magnetic protection during this era. It is wound by the crown and powers the watch through a mainspring that Hamilton advertised as unbreakable, which was a meaningful selling point at the time. At this age, the movement performs best when freshly serviced with clean oil, as dried lubricants are the most common cause of timekeeping problems in these calibers.