rear of the printer rear of the printer rear of the printer rear of the printer rear of the printer The rear of the printer displays the following: 1. USB port - Attach a USB cable. 2. Parallel port - Attach the parallel cable 3. LIO Adaptor Slot - Install an optional HP JetDirect print server/Internet connector LIO module 4. Power input - Attach the power cord.. 5. Rear access panel - Remove this to clear paper jam. Remove the rear access panel to install the optional auto-duplex unit. Rear access panel required for straight paper path (rear manual feed). 1 - 12 hp confidential tour of the product