Heuer Solunar

About this reference

The Heuer Solunar reference 279.603 (often associated with the 87304 case designation) was produced during the mid-to-late 1970s and is no longer in production. Collectors value this reference for its specialized tide-tracking complication, which utilizes a bidirectional internal bezel and a pusher at 4 o'clock to align high and low tide times. The watch features a 45mm stainless steel cushion case and houses the automatic Valjoux 7733-based caliber 2791. Its place in Heuer history is defined by its niche functionality for mariners and its distinct colorful dial layout. On the secondary market, these timepieces typically trade between $3,500 and $6,000 depending on condition and the presence of the original steel bracelet. A notable production detail is that this model was the successor to the 1940s Solunar, representing the brand's final mechanical effort to integrate lunar-tide cycles before the quartz era.