Tractor Hour Meter HR400001One New Aftermarket Replacement Hour Meter for Tractors and Agricultural Equipment This universal hour meter (HR400001) is a mechanical digital gauge designed to track engine operating hours on tractors, riding lawn mowers, and other agricultural equipment. Mounted in the instrument panel, it helps operators stay on schedule with fluid changes, filter replacements, and other routine service intervals. Compatible with 6 volt, 12 volt, and 24 volt