Glycerin. Glycerin is an ingredient that can be found in many beauty products because of its moisture locking properties. It is a form of sugar alcohol that is available naturally in vegetable oils and can also be the byproduct of soap making.
Definition of wheel and axle : a mechanical device consisting of a grooved wheel turned by a cord or chain with a rigidly attached axle (as for winding up a weight) together with the supporting standards
A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built off the shelf performance-oriented wheels. Bicycle wheels are typically designed to fit into the frame and fork via dropouts, and hold bicycle tires.