Hamilton Khaki Field Mechanical Power ReservevsMarathon Steel Navigator SSNAV Auto

The Hamilton Khaki Field Mechanical Power Reserve is noted for its 40mm sandblasted case, filling a size gap in the Khaki Field line. It features a new H-23 hand-wound movement with an 80-hour power reserve and a functional power reserve indicator at 9 o'clock. The case is 11.95mm thick, which is described as noticeably thicker than other Khaki Field models, and its proportions differ from classic manual-wind versions. The movement includes a slipping spring to resynchronize the power reserve indicator after shocks. Overall, reviewers appreciate the addition of the power reserve complication to the hand-wound model, though one reviewer noted a preference for a contrasting color on the indicator.

The Marathon Steel Navigator SSNAV Auto is praised for its high-accuracy quartz movement, with owners noting its comfort and reliable performance. Reviewers highlight its functional tool-watch appeal, featuring a sandblasted steel case, tritium tubes for constant low-light visibility, and 100-meter water resistance. One owner finds the 41mm case runs a bit small. The Marathon Steel Navigator SSNAV Auto utilizes an ETA F06.412 quartz movement with a claimed accuracy of +/- 10 seconds per year and includes a GMT bidirectional bezel. Overall, owners and reviewers rate the Marathon Steel Navigator SSNAV Auto highly for its comfortable wear and dependable, high-accuracy quartz movement.