Material: PU leather 100% Quality Guarantee, Brand new leather dog collar Studded Spikes Studs cool design as the pictures show XSmall size for Neck 8-10.5 inch (21-27cm), Small size for Neck 10.5-13 inch (27-33cm), Medium size for Neck 12.5-15 inch (32-38cm), Large size for Neck 14.5-18.5 inch, (37-47cm) Note: Before you order,Be sure your dog's neck is suitable for this size (That's very important).