Hamilton Khaki Aviation Converter Auto ChronovsSpinnaker Croft Mid-Size Skeleton

The Hamilton Khaki Aviation Converter Auto Chrono is widely described as a large 44mm pilot's watch with a functional slide rule bezel. Reviewers note its well-finished steel case, featuring a robust satin-brushed finish with polished accents and chamfers, and a legible blue sunray dial with applied Super-LumiNova markers and old-fashioned hands. It is powered by the H-21-Si automatic chronograph movement, an upgraded ETA-based caliber with a silicon balance spring for anti-magnetic properties, offering a 60-hour power reserve. The watch is rated to 100m water resistance and features a bi-directional slide rule bezel with graduations printed under K1 mineral glass for scratch protection, which is easy to manipulate due to its deeply notched steel design. Some find the slide rule bezel complicated to use without a manual. One owner notes its character does not appeal as much as other slide bezel chronos.

The Spinnaker Croft Mid-Size Skeleton is noted for its 40mm steel case, sapphire crystal, and 150m water resistance. One owner reports strong performance from the TMI NH70 movement at -3 seconds per day, with very nice lume. On balance, owners find the Spinnaker Croft Mid-Size Skeleton to be a pretty nice option, particularly for its movement performance and lume.