The K3969-1 Connection Kit is used to attach extraction nozzles and/or fume guns to the X-Tractor 5A and 8A. The VV-50 valve is the main distribution valve and has three outlets; two with an outside diameter of 50 mm (2 inch) and one with an O.D. of 76 mm (3 inch). The S20591-8 Hose to Tube adapters included in the kit allow for the connection of 1-3/4 inch (45 mm) I.D. hoses to the four 50 mm (2 inch) outlets of VV-50 valves.