HB COMPETITION ROCK CRAWLER TIRE. Grab the rocks and climb the toughest ascents with the amazing HB Rover tires. These tires are taking the crawling community by storm, because of their awesome flexibility, tall profile and unique inner foam characteristics. Extensively tested in real competition by the HPI/HB crawler team, rock crawling fanatics have been raving about the Rovers since they first saw it in action. Now that they have the chance to try it on their own rigs, the word has been spreading and the verdict is: TREMENDOUS. The more these tires are run, the better they perform, on all types of rock: granite, sandstone, and more. Even in wet conditions they will excel - just give them a try.