The roller capacity refers to the maximum load a single roller can support on the conveyor system. Load capacities listed are based on the between frame length of the conveyor roller, actual load ratings for the roller bearing, tube deflection and shaft deflection. Load capacities for precision roller bearings allow for 3/4 of a degree of shaft deflection at the bearing. For commercial unground bearings it is 1 degree. When selecting a roller for a specific material handling application, a good rule of thumb is to allow 25% more capacity than the heaviest product being conveyed. To ensure smooth conveyance of product, Indoff recommends that a minimum of 3 conveyor rollers be in contact with the conveyed product at all times.