【Soft Silicone Cap for Better Protection】: The receiver contact point uses the latest soft silicone material, and the flexibility of the silicone cap can better protect the dog’s skin. The non-removable silicone stopper not only prevents it from falling off and getting lost, but also from being swallowed by dogs. 【Adjustable Collar for Better Fit】: The collar is made of a material premium quality that is gentle on your dog. This dog training collar is ideal for small, medium and large dogs from 6.80 kg to 52.45 kg. The collar also has reflective markings.