Designed to vent the accumulation of troublesome air wherever it can be trapped. These non-ferrous automatic air vents are 4-3/4" x 2-1/4", 3-3/16" x 1-1/2" and 4-1/16" x 2-3/16" (height and width), respectively, and are rated for a maximum operating temperature of 240 deg F at pressures of 150, 35 and 75 PSI, respectively. The No. 87 has a combination of 1/2" FPT/3/4" MPT connection, whereas No's. 67 and 7 have 1/8" MPT, and FPT connections.
Bell & Gossett Automatic Air Vent, 1/8 in Nominal, FNPT, 75 psig Working, 240 deg F, Brass, 2-3/16 in W x 4-1/16 in H