Official Q&A: VEXU 2022-2023: Spin Up

Under VUR6, it's stated that a spring is "any device used for storing and releasing elastic potential energy". Under the definition, would COTS rubber and polyurethane timing belts fall under the category of springs, since their primary function is power transmission via the use of elastic tension? Additionally, would COTS rubber and polyurethane belt extrusion be legal under VUR4? Other legal materials - such as surgical tubing and aluminum extrusion - go about the same manufacturing process, so it would make sense that extruded rubber and polyurethane belt would fall under that rule as well. Thanks!