OPTIONAL SIZE -- Size S: Neck Cir: 5.9-9.1inch/15-23cm; Neck Dia: 3.1inch/8cm; L*W: 22*23cm; Size M: Neck Cir: 7.9-11.8inch/20-30cm; Neck Dia: 3.5inch/9cm; L*W: 27*27cm; Size L: Neck Cir: 12.6-17.7inch/32-45cm; Neck Dia: 5.3inch/13.5cm; L*W: 40*40cm. (Please kindly measure the neck circumference of your pet before order) SCRATCH & BITE RESISTANT -- This inflatable collar is designed to protect your pets from injuries, rashes and post surgery wounds, it will prevent pets from biting and licking their injured area or surgical site and promote recovering from surgery or wounds. DURABLE & ADJUTABLE -- Made of high quality material which will not be broken or leaking valve by pet scratched; and the velcro buckle can be adjustable to better fix around your pet 's neck. SOFT & COMFORTABLE -- Inflatable design and the soft outside material will bring comfortable experience for your pet dog, never hurt your pet and it does not block your pet's vision, they can eat, drink, sleep and play normally. EASY TO USE & STORE -- The recovery e-collar can be deflated and store it in a small space when no use and there is a zipper opening on one side, you can take the bag out and wash the outside cloth, it is very easy to use and store.