Description: Infrared sensor timer, very small and exquisite. After receiving the goods, please prepare 2x AAA batteries(Not Include). Install the battery into the battery compartment and turn on the side power switch. The timer display lights up and a buzzer sounds, indicating that the timer is ready. Put your hands on the infrared sensing area 0-4cm on both sides of the timer. Timing starts when both hands leave the sensing area and stops when the hands return to the sensing area. Press the right round button once to clear the timer and restart the timer. Power switch on the side: Right button: Press once to clear the timer; Press and hold for the buzzer switch, and there is a prompt on the screen. Left button: View timing results. Single press View the results of the last 5 times (Remove the first and last time, the remaining average score) Double press View the results of the last 12 times (Remove the first and last time, the remaining average score) Press 3 times Show all time-averaged results Specification: Size(LxWxH): about 6.5x1.6x7.5cm/2.55x0.63x2.95inch Package Includes: 1x Timer 1x Lanyard : Please allow slightly 0-1cm difference due to manual measurement. Colors can appear different depending on light and how the listing is viewed. Thanks for your understanding and attention. Wish you a pleasant shopping experience!