Green nylon adjustable collar with plastic buckle. - Color: Green - Material: Nylon - Adjustable Size: Yes, I believe so. - Buckle Type: Plastic buckle Thank you for looking. I accidentally bought the wrong size. Measuring the collar as it is, without stretching it, it's about 59 centimeters. It's a type that reflects light at night. It's a bright, yellowish-green color. I opened the bag once to measure the length, so I hope you understand.