There are two versions of led collar.
1. In the USB charging version, recharging after the light becomes weaker will help improve the battery life.
2. Button battery version CR2016 button battery x 2, please replace the spare battery when the power is turned off.
Size width neck circumference
XS 2.0 cm 28-40 cm / 11 -15 inches
S 2.5 cm 35-43 cm / 13 -16 inches
M 2.5 cm 40-48 cm / 16-18 inches
L 2.5 cm 45-52 cm / 18-20 inches
XL 2.5 cm 52-60 cm / 20-23 inches
Triple flash mode first click_quick flash
Second click_slow flashing
Third click_ stable light