ProTimer Plus (Trademark) automatically turns your pump on and off for desired circulation and aeration. Can be connected to an existing switch in your boat (3 position, center off recommended). ProTimer Plus (Trademark) has all the features of ProTimer (Trademark), plus it comes with a master control switch to control on, off or timed livewell operation.1 Minute on/adj 1-minutes to 12-minutes off. Includes 3 position rocker switch for off, timed or constant run. For use with any livewell recirculation pump or Flow-Rite valve system with "RECIRC" mode. Auto operation increases fishing time. Ideal for tournament fishing. Adjustable time delay feature to meet specific ambient conditions. Helps to increase battery life. Color coding promotes easy operation. Self-adhesive backing for easy installation. eliminates screws. Weather resistant poly coated circuit board. Material: Plastic.