SM Arnold's  most aggressive and durable Tire & Sidewall brush .  
 
It's densely packed Brass Wire bristles are staple-set into a plastic foam block making it safer for your vehicle’s finish. SM Arnold's 85-637 Whitewall/Sidewall Tire Brush has a set of full .75" brass bristles embedded in a chemical resistant foam plastic block which were crimped to give you added strength when scrubbing the toughest grit found on the clingy and porous surface that rubber can be