Dual Fuel Level E-F 0-178 ohm, 2 1/4" square, 8-30 vdc, 0 ohm E = 36 ohm 1/4 = 81 ohm 1/2 = 127 ohm 3/4 = 178 ohm = F, red arc E-1/8  Use with 0-178 ohm float type senders sold separately not by WESTACH, Light kit 186-12A2 sold separately