Economic order quantity calculator / purchase discount evaluator

Circular calculator wheel. Consists of white plastic base with black numerical markings with two rotational discs attached by a central metal eyelet to each face. The obverse, to be utilised as a purchase discount calculator, has one clear plastic disc with green markings and one smaller white plastic disc with black numerical markings. The reverse, to be utilised as an economic order quantity calculator, has one white plastic disc with red numerical markings and one smaller disc with a pointer and black lettering. With plastic pouch holder inscribed, ' Economic Order Quantity Calculator'.