The HOBO U20L water level logger from Onset Computer Corporation provides precise water level and temperature monitoring. It has 0.1 percent measurement accuracy; a polypropylene housing for use in both fresh and salt water; a self-contained, non-vented design for convenient and hassle-free deployment; and a durable ceramic pressure sensor that withstands freezing. It is ideal for use in wells, streams, lakes, wetlands and tidal areas. It utilizes HOBOware Pro software, which provides easy conversion to accurate water level reading, fully compensated for barometric pressure, temperature and water density. It is available in three models for depths up to 13, 30 and 100 feet. 800/564-4377; www.onsetcomp.com.