Smooth, polysulfone body of Model ELS-1100FLG slips through 3/4 in. hole in thin-walled plastic or steel tank and tightens from outside. Threadless design prevents bacterial breeding and contamination. Electro-optic sensor minimizes tank intrusion. Sensor monitors liquid level with ±1 mm accuracy. Viton gasket, 1/8 in. thick, handles vessel pressures up to 150 psi.