Graces with Indigenous artwork by Patricia Nakamarra Oldfield of the Warlukurlangu Artist Aboriginal Corporation, 10% of sales go back to the artist. Designed for greyhound and sighthound breeds, these martingale collars help control your dog on a walk without causing stress on their delicate necks. Graced with the Indigenous artwork - Ngama by Patricia Nakamarra Oldfield with 10% of sales going directly back to the artist. Our collars are made from cotton canvas that has been wrapped around nylon webbing and come in 2 sizes. Please measure up your dogs neck to ensure you choose the right size for your dog: Sizing (please measure your dog's neck to choose the right size) Medium - 36cm to 42cm (4cm wide) - Whippets Large - 38cm to 46cm (4cm wide) Greyhounds Watch our demo video here to fit your dog