1. Material: plastic + electronic components
2. Power supply: button battery
3. Silicone material keys, comfortable hand feeling
4. Side modeling rounded, smooth and not cut hands
5. With a pull ring, can be hung on the key or bag, convenient to go out and carry
6. Transparent flip cover design, not easy to accidentally contact the button
7. Replaceable battery, longer service life
8. Size: about 62 x 37mm