What is Timing Device, Surface mount tuning fork crystal, Wireless timing system

 CSM-7X Series 7.3728 MHz ±30 ppm 20 pF -10 to +70 °C SMT Quartz Crystal

https://www.futureelectronics.com/p/electromechanical--timing-devices--crystals/ecs-73-20-5px-tr-ecs-inc.-2022144