SCALPMASTER 11 ROW WIRE BRISTLE BRUSH # 126
When I showed my English Springer Spaniels in conformation, I swore by the Scalpmaster brush for grooming my dog's feathering. The ESS feathering can take a beating from the elements and excessive grooming for the ring.
In fact, most of the handlers used the same brush. The bristles are very thin and smooth without any ball tips and set in a flexible cushion pad. The pins will give when you come across small snarls and tangles, but can withstand the coarseness of the hair strand.
When I bought Sam, I bought a new scalpmaster for his mane and tail and I am very pleased with how it works on him. I do not have hair come off into the brush unless I am a dork and don't take my time.
If you clean the brush, do not let it sit long in bleach water or other harsh disenfectant. You don't want to compromise the cushion's flexibility (harsh lesson learned here).
Here is where I purchased mine. The seller provided quick response to shipping and I was happy with my overall experience. Scalpmaster Brushes
I am a fan of Cowboy Magic and use it liberally a few times a week. I don't believe it is sold as a "hair growth" chemical, but I find it does wonders to strenghening Sam's tail and mane and also protecting it from the elements. I can feel it in the hair up to 5 days without rain. Since using it regularly, I have noticed his tail hair has less broken ends and fly aways and seems to be growing in both bulk and length.