Limited space is one of the main difficulties of this application. The DS8100 material-handling scanner with mounting flexibility and small size provides the most advanced modular, plug & play design solution available today in tunnel scanning. The labels are supplied by customers in different ways and vary in quality, according to the source and method of printing. As parcels are unloaded from the trailer, the scanner collects the bar code data from the scanner network, compares it with the last 5 entries in the log file. The facility uses 16 tunnel systems and 3 manual presentation overhead stations. Each tunnel consists of four to eight material handling scanners according to the reading requirement for each conveyor. Three system controllers (Industrial PCs) monitor all the scanning systems linked to the central computer for data transfer.