Rotation Gear Reduction Box : The mechanism of an aerial device that transfers hydraulic or electric power to the rotation gear, creating the torque necessary to rotate the turntable
NFPA 1911 Standard for the Inspection, Maintenance, Testing, and Retirement of In-Service Automotive Fire Apparatus, 2007 ed. https://www.iafc.org/files/1EVM/evms_NFPA1911_1071 andEVT.pdf, (Std: Insp, Maint, Tst and Retirement of In-Srvc Automotive Fr Aptus - Amer) {415 NFC}