Your dog needs more than a harness Benji8 , he needs proper training. Training that should have started long before he reached the age of 13 months. Has he been properly socialised? What sort of anxiety does he have ?
It would be a valuable start for you to get a professional dog trainer or behaviourist to evaluate him so you know what you're dealing with. Even local dog training classes would be a help.
You can buy any old harness to be fair but unless you use it effectively coupled with decent training it wont be much help.
Changing from a Manual car to an Automatic after driving manual for around 50 yrs


