Hamilton Jazzmaster Open Heart Auto 42mm Steel
How might this watch look on my wrist? A 3D representation of Hamilton Jazzmaster Open Heart Auto 42mm Steel. Check retailer page for actual dimensions and specifications.
Scroll or drag to turn the wrist. Shown to scale on a typical men’s wrist (17.5 cm), lug to lug 48.3 mm (measured from the photo).
This 42mm stainless steel Jazzmaster features an open heart aperture that reveals the automatic H-10 movement at 12 o'clock. The midnight blue dial includes applied indices and a date window at 3 o'clock, with the movement's Nivachron balance spring visible through the transparent caseback. The H-10 calibre offers an 80-hour power reserve, whilst the case provides 5 bar water resistance. A polished and brushed stainless steel bracelet with fold-over clasp completes the watch.
This timepiece bridges classical Jazzmaster aesthetics with contemporary watchmaking through its open heart construction and extended power reserve. The Nivachron technology represents an improvement over traditional balance springs in terms of stability and isochronism. The substantial 42mm diameter and robust steel bracelet suit those preferring a present wrist presence.
The Hamilton Jazzmaster H32705140 is listed on WatchShopper as a 42 mm stainless steel automatic watch with a midnight blue dial. It runs on the H-10 calibre with an 80-hour power reserve and comes on a stainless steel bracelet. On 19 October 2026 the lowest UK price was £1,065.00 at Goldsmiths, in stock, with free delivery and 14-day returns.
At £1,065 this watch is mid-priced for an automatic watch with a 40–44 mm case: 46% of the 1,388 we track from every brand cost less. 81% of the 130 Hamilton watches we track cost less than this one. This is the 16th cheapest of the 22 versions of the Jazzmaster we list.
