Panasonic EX-F1 amplifier built-in sensor saves space as there is no need to install a separate amplifier. Just attach it on a pipe with the tying bands. The position can be easily changed with the release lever even after mounting, so that there is no need to cut the tying bands. Panasonic EX-F1 is very cost-effective. The operation can be checked at a glance from different directions. Either Light-ON or Dark-ON can be selected by a switch. This is useful to check the operation during installation because it forces the output to be turned ON or OFF even without the liquid being inside the pipe.