yea
They are made from rubber but on the sides they have made bumbs so it can move across the ground easy, hope that helps.
Tires that are recycled can be made into Rubber Mulch! http://www.rubberecycle.com/ creates rubber mulch which can be used for landscaping and to make your playground safe, it's an environment...
Special hardened rubber.
rubber. compacted rubber to be specific. pure sythetic rubber. mostley made in checkslovkia