Wilkins is a backflow preventer manufacturer. They produce all types of backflow preventers including pressure vacuum breakers, double check valve assemblies, double check detector assemblies, reduced pressure assemblies, and reduced pressure detector assemblies. Some of their most popular models are the 720A, 420XL, 950XL, 950XLT2, 350XL, 350AST, 350DA, 350ASTDA, 975, 975XL, 975XL2, 375, 375XL, 375AST, 375DA, and 375ASTDA.