Provide maintenance and repair support for the Rockwell Collins 721S series radios. The contractor shall perform maintenance and repair to all the systems and return to factory recommended specifications, which will include system testing, alignment checks, and equipment cleaning procedures. The contractors shall install any system software or firmware upgrade required to bring the equipment current for system integrity, security, and functionality. The contractor shall provide operational testing and alignment, as applicable, on infrastructure and fixed network equipment to ensure the equipment meets original manufacturer’s specifications. Contractor shall remove any oil, dust, and/or foreign substances from the equipment, clean filters, if applicable, and measure, record, align, and make all applicable equipment parameter adjustments in accordance with best commercial practices.