Long range signal reception The reception range can reach 30-200 meters/656 feet, stable in open areas. (Practical distance depends on the environment. Extended support by adding an amplifier.) Made of high-quality materials, sturdy and durable. Easy to use, the call button is designed to be user-friendly and can be used easily by anyone. Compact design Small size, light weight and round shape make the pager comfortable to hold and easy to carry. With calendar display, rechargeable battery. Modulation Mode:ASK (AM) RF Frequency:433MHz Working Chip:Learning Code Power Supply:Button Cell Colour:Black Material:Plastic Package Contents: 1 * Watch 1 * Charging Cable 10 * Call Button Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.