These blowers offer a range of high volume air intake or extraction for engine room, fuel compartment, galley, or head compartments. Flexmount blowers have both inlet and outlet ports designed for slip-on flexible duct connections. They are ideal when an "in-line" installation of a blower is preferred. Length is the dimension along the fan motor axis (C in diagram) May be rotated in the mounting bracket to permit installation with the discharge port in any direction DC models are ignition protected - comply with USCG 183.410 and ISO 8846 MARINE AC models are not ignition protected Note the 35515 replacement blower housing is 2 part numbers