The Betts VR45784BU is a 3.5-inch emission collection hood designed for bolted style vapor vents on tank trailers. This vapor recovery hood provides an economical means of connecting the positive vapor vent to the vapor rail during loading and unloading operations. The hood is made from ozone and ultraviolet resistant ntirile, and includes a mounting clamp, outlet clamp, and coupling. The VR45784BU features a collapsible design that protects product retention in the cargo tank during rollover incidents while maintaining a secure connection to the vapor collection system.