Bridgestone Battlecross E50 Tire - 90/90-21 M/C 54P FrontBuilt specifically with the hardcore Enduro rider in mind, the Battlecross E50 from Bridgestone is the most versatile offroad tire in the Battlecross line up, able to traverse multiple surfaces in one ride. Castle Block Technology, increased block rigidity, coupled with a new front and rear tread pattern and bunker technology improves cornering grip and offroad traction.