Abstract: A treadmill is described herein that utilizes a simple mechanism that absorbs impacts delivered to the treadmill by a user during use. The treadmill includes a frame for supporting an endless belt. A forward structure supports a first end of the frame. A pivoting structure supports and the second end of the frame and provides impact absorption. The pivoting structure includes a pivot arm that is pivotally affixed to an underside of the frame. A roller is mounted on a roller axle proximate the free end of the pivot arm. A spring is provided that has a first end in communication with the frame and has a second end in communication with the pivot arm for biasing the pivot arm away from the frame. Preferably, the spring surrounds a limiter that limits the maximum amount of travel that the pivot arm can extend away from the frame.

Abstract: Pencils that have an outer sheath comprising a base elastomer and reclaimed rubber for enclosing an inner marking core therein. The base elastomer provides a vulcanizate with basic physical and environmental resistant properties including at a minimum elasticity, flexibility, and relative impermeability to water and air while the reclaimed rubber advantageously extends the base elastomer to reduce cost and help reduce quantities of existing environmentally harmful waste. By not incorporating wood in the sheath, the present invention does not contribute to deforestation or consumption of a natural resource, but to the contrary, describes an efficient use for used tires. In addition, the pencils of the present invention are easier to manufacture than wooden pencils and generate less health hazards.