What is a rubber pin brush? If it has balls @ the end of the pins, those are a no no. The hair can get snagged between the ball & pin & cause breakage making the hair frizzy. It's best to shave the arm pits (along w/other high rubbing areas like inner thighs & belly), those areas are very sensitive to them. You can also snip the hairs off w/a blunt nosed scissor. If he's really badly matted to the skin over 30% of his body, then I would shave him down (while it's still warm) & start over. It would be puppy hair that u're getting rid of anyway. His adult hair should come in nicely in the next few months. Depending on how his adult hair turns out, you can decide then to either grow it or keep him in a puppy cut...which will be easier on both of you!
