Johnson Controls P74EA-8 Differential Pressure Control, SPDT ( Snap Acting ), 2 Psi to 26 Psi Adjusatble Range Pressure Differential, 3.5 Psi Fixed Switch Differential, 36" Capillary with 1/4" Flare Nut, Brass Bellows, 16 Amp 208-600 Vac/Vdc