Competitors fall into 2 categories:
1) New replacement tires:  Purchased through online retailers (Tirerack.com) and retail chains (Pep Boys, Discount Tire). 
2) Retreaders: Most light truck retreaders are "mom & pop" operations that operate locally.  There are a couple regional retreaders that distribute in their area.  We are not aware of any other light truck retreaders that sell direct to consumers online or over the phone with a national reach.  Regional retreaders include: Tire Recappers (Nashville), Eastern Tire (Nova Scotia), Day & Night Tire Remanufacturing (FL).