A differential feedback system that minimizes even order distortion of a differential circuit. The composition is applied to food products, such as fruits, vegetables and nuts, to provide an edible protective coating for the food products. The controller has a service that can either be enabled or disabled by a system administrator. Pad dyeing and yarn selection produces contrast between a front layer and revealed portions of an intermediate layer. The sound-emitting squeaker device remains free to move throughout the internal space of the internal skeletal member.