The Jaeger Lecoultre 497/1 watch movement features a pin lever escapement, which is a common type of escapement used in mechanical watches. The pin lever escapement consists of a simple lever with a pin that engages with the teeth of the escape wheel, allowing the movement to regulate the timekeeping by controlling the release of energy from the mainspring. This function is characteristic of the Jaeger Lecoultre 497/1 watch movement.