1955 Hermès Landeron 51 Chronograph

Date

A feature that displays the current day of the month, typically in a small window on the dial, commonly placed at the 3 o'clock or 6 o'clock position.

Mechanique Chronograph

A chronograph watch powered by mechanical (hand-winding) movement, combining both timekeeping and the ability to measure elapsed time with a stopwatch function.

Water Resistant

A basic level of water resistance that protects the watch from accidental splashes, such as rain. It is not designed for submersion or exposure to water beyond light splashes.

Tachymeter

A scale on the dial of a chronograph that allows the wearer to calculate speed based on time and distance, typically by measuring how many seconds it takes to travel a fixed distance (e.g., 1000 meters).