The Citizen 4-L01919 watch movement utilizes a pin lever escapement system. This type of escapement is characterized by a simple design that relies on a pin lever to transfer energy from the mainspring to the balance wheel. It is commonly found in entry-level mechanical movements due to its cost-effective nature. The pin lever escapement provides accurate timekeeping, although it may be less robust and may require more frequent servicing compared to higher-end escapement systems.