The Hydrotek LIGHTSPEED FLIP20 is an automated light switching unit which allows you to control 20 lights from 10 ballasts (10 lights on at a time). These units work with ballasts of any voltage and are heavy duty and built to last. 20 reflector plugs on one side, 10 ballast cords on the other side. Save money on your ballasts - use half as many! 120V power cord works with any 120V timer. Compatible with standard style reflectors and ballasts. Made in Canada.