Liquid level gauges guard against low oil levels and monitor tank contents for level, clarity, and temperature. They come in many materials — nylon for pressures to 125 psi and temperatures to 205°F; milled aluminum for pressures to 175 psi and temperatures to 225°F; flexible vinyl for pressures to 30 psi and temperatures to 180°F; steel channel for pressures to 125 psi and temperatures to 225°F; and broad face nylon for pressures to 50 psi and temperatures to 205°F.

OilRite Corp., (920) 682-6173, www.oilrite.com