Proflow Water Neck, Billet Aluminium, Swivel Blue Anodised, 45 Degree, SB For Ford 289-351W - PFETH-804BLPart Number: PFETH 804BL Proflow's billet thermostat housings not only look good, but they also get rid of leaky paper gaskets thanks to their O ring seal design. You can choose the conventional vertical housing or the high tech 360 degree swivel housing. They're available straight up or with a 0, 45, or 90 degree angle and come complete with stainless hardware. Please use plug PFE814 01 if not using the heater hose outlet.