Model 2151A (photoelectric sensor) and model 2151TA (photoelectric sensor with thermal) can be used with a variety of adapter bases in several wiring configurations and voltages. Features include: low current draw, stable performance in high air velocities, built-in tamper resistant base design, remote LED option, removable cover, built-in test switch and the ability to obtain sensitivity readings using the CSENS-RDRA infrared reader.