The 301.SX.1170.RX is the 44 mm steel Big Bang, in the line of the chronograph with which Hublot ushered in the 'Art of Fusion' in 2005.
The watch carries all the features that made the Big Bang known: a layered case with a bezel bearing six H-shaped screws, composite layers on the sides, polished and brushed surfaces and a rubber strap.
Inside is the HUB4100, a self-winding chronograph calibre with date that Hublot builds on the basis of a bought-in movement, unlike the in-house Unico calibre of the later Big Bang Unico. The watch is water-resistant to 100 metres.
Because this Big Bang has been in circulation for many years, pre-owned examples vary widely in condition. We look for polishing marks and rounded edges on the steel case, at the H-screws and the composite layers, which can weather over the years, and at the pushers and the crown.
We test the chronograph and ask about the service history. The rubber strap has often been replaced at some point; we state whether it is original. We compare reference and serial number with the guarantee card.
