These maintenance-free thermometers operate on solar power in light levels above 100 LUX, and use a battery back-up below 100 LUX. The calibration adjustment is on back of unit. The 48"L cable has no lead-containing pigments.
Use panel-mount thermometers for front flange attachment.
Use wall-mount thermometers for rear flange attachment.
U-clamp thermometers are for mounting without flange attachment.