Harnesses over collars.

One of many articles treating about advantages of harnesses over collars & slip leads. 
Our experience shows clearly that harness is the best possible choice, specially for dogs who pull on the leash!

https://dogmantics.com/is-it-harmful-to-attach-a-leash-to-your-dogs-neck-2/?fbclid=IwAR1A8z-IxYRfE009PheqowCpNbWZlE-3RGtdmPETHWn4dBQJ7KLWs40sBXk