This extension cord is *UL listed* and is compatible with most major brand ballasts and reflectors including Hypoteky and GRO1y. It's available in 10, 15, 25, and 50 ft lengths This extension cord is *UL listed* and is compatible with most major brand ballasts and reflectors including Hypoteky and GRO1. It's available in 10, 15, 25, and 50 ft lengths