The invention is a cleaning material for cleaning printing machines. Capacity is increased by configuring the base station to operate at two different, non-interfering frequencies within each sector of the cell. The body portion has a pair of legs that act to retain the body portion within the substrate and which incorporate an interference control mechanism that controls the force required to insert the pin portion of the fastener into the body portion. Items that are ordered somewhat more frequently than those in the slowest group are replicated in multiple pods across the distribution center. In one embodiment, the package includes: a substantially planar piezoelectric substrate, SAW circuit conductors located over the substrate and a passivation layer located over the SAW circuit conductors, the substrate and the passivation layer cooperating to form a hermetic seal to isolate the SAW circuit conductors from an environment proximate the package.