These rubber Seat poppet Type regulators are designed primarily for main burner and pilot load applications where precise control of tiny flows is an essential operating requirement. Certified (.15 cfh). housings are of high strength aluminum die castings. All models, with the exception of "D" Suffix models, have been tested for multi-poise mounting and may be installed in any plane or angle without restriction. "D" Suffix models are to be mounted horizontally. Other than normal upright position will result in slight difference of Outlet pressure. They may be used with natural, manufactured, mixed, LP, or LP gas-air mixture. Made in United States. Manufactured by Maxtor company.