It may be limited to 1,999 individually numbered pieces, but that's the only limitation the Khaki Takeoff Auto Chrono knows. Count up with the chronograph movement or set the bi-directional turning flange to record a countdown. This is a technical take on a contemporary pilot's watch that was created to meet the needs of the Air Zermatt Swiss mountain rescue service- and it's ready for take off.KHAKI AVIATIONThe Khaki Aviation collection perfectly displays Hamilton's technical know-how when it comes to creating reliable watches for pilots and urban aviators. SELF-WINDINGWrist movements cause the inner rotor to swing, transferring energy to the mainspring, and powering your timepiece.STAINLESS STEEL CASEA highly resistant alloy composed of steel and chromium. It can be worked to resemble a precious metal. It is nearly impervious to rust, tarnish, and corrosion.SAPPHIRE CRYSTALSynthetic sapphire crystal is a tough scratch-resistant material, only diamonds could leave a mark.H-31 CALIBERA powerful automatic chronograph movement featuring an extended 60-hour power reserve.WATER RESISTANCEYour timepiece is resistant up to 5 bar (50m) / 73 psi (164 ft).