Proflow Water Neck, Billet Aluminium Swivel, Black Anodised, 90 Degree, SB & BB Chev - PFETH-803BKPart Number: PFETH 803BK 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.