Features: Type:Pet Recovery E-Collar Material:Nylon + Cotton Size:XS-2XL Suitable for Cat Dog Notice: Due to the different monitor and light effect,the actual color maybe a slight different from the picture color. Please allow 2-3cm differs due to manual measurement . Size: XS Neck(cm/in): 16/6.3-21/8.3 Diameter(cm/in): 24/9.4 Thickness(cm/in): 2.5/1 Size: S Neck(cm/in): 20/7.9-26/10.2 Diameter(cm/in): 26/10.2 Thickness(cm/in): 2.5/1 Size: M Neck(cm/in): 25/9.8-30/11.8 Diameter(cm/in): 33/13 Thickness(cm/in): 2.5/1 Size: L Neck(cm/in): 30/11.8-35/13.8 Diameter(cm/in): 39/15.4 Thickness(cm/in): 3.0/1.2 Size: XL Neck(cm/in): 33/13-40/15.7 Diameter(cm/in): 41/16.1 Thickness(cm/in): 3.0/1.2 Size: 2XL Neck(cm/in): 40/15.7-50/19.7 Diameter(cm/in): 56/22 Thickness(cm/in): 3.0/1.2 includes:1 xPet Recovery E-Collar