A DishPro Single LNBF looks at one orbital location. It is the only DishPro LNBF appropriate for an 18” (or "DISH 300”) dish antenna. It would be used alone in 61.5º and 148° installations. Two DishPro Single LNBFs can also be used on a 20” (or "DISH 500") dish antenna (must also use a DP34 switch).