It is also an excellent way to ensure both you and your pet's safety. Features: Material:nylon strap Color:Blue;Red;Orange;Yellow;Green;Pink. LED Powered by 4pcs CR2016 (include) Cell Button. Battery life:60 hours. 3 light modes:Continuous on,Slow flashing,Fast flashing(with switch to select). Note: Please make sure to measure your dog for accurate sizing before purchasing to ensure the perfect fit. The actual color of the item may slightly vary from the pictures due to the light and different monitors. The size is manual measurement, there may be 2-3cm error. Please understand.