I have a x-large dog harness I wear, its better to use with a leash cuz it takes the pulling off the neck and equally spreads it across the chest, making it more of a pressure instead of a restriction. Master keeps my collar loose but he tugs on it sometimes only cuz I enjoy breath play. I actually haven't heard or found any dangers in puppy play, other then the walking on all fours, which if you do it on hands and feet instead of hands and knees, it takes a lot of practice and training since it uses muscles not normally used