A separator and composting unit for a sewage treatment system. The computing device receives a selection of a set of one or more screens from the owner of the mobile device. Each merchandise supporting unit has a front side and an opposite rear side, and a pair of spaced apart locator protrusions extending outwardly from the rear side which are receivable in corresponding openings in the indexing members and are engageable with the resilient locking clips to secure the merchandise supporting units to the frame. It also has the ability to keep the wireless traffic separate from the wired traffic.