Hamilton’s aviation history goes all the way back to 1918 when the watchmaker made timepieces for pilots as the official timekeeper for U.S. airmail flights between Washington, Philadelphia and New York. To celebrate the 100 years since that debut, the brand is releasing a limited edition watch: the Khaki X-Wind Day Date Automatic Chronograph.

Being based on the standard Khaki X-Wind, it incorporates a mechanical chronograph movement with a drift-angle calculator (a world first) into a rugged case, but Hamilton gave the H-21-Si movement inside now has a silicon hairspring, a first for a chronograph from the brand. This means that in addition to being resistant to shocks and magnetism — an essential feature for pilots who regularly come into contact with strong magnetic fields — it’s capable of chronometer-level accuracy within the Official Swiss Chronometer Testing Institute’s (COSC) strict standards.

In addition to the new innards, the watch’s black dial now features tan-colored accents on the numerals, hands and sub-dials, giving this modern watch a bit of vintage flair. It comes paired either with a beige leather strap or a stainless steel bracelet, the former retailing for $2,595 and the latter $2,645. Given that this is a limited edition of just 1,918 pieces with a chronometer-certified chronograph inside, that’s a heck of a deal.