Season chicken over night with hot sauce and rosemary and keep in fridge.
In a large (5- to 6-quart) deep heavy kettle heat 6 cups oil until a deep-fat thermometer registers 380°F Just before oil reaches 380°F, pat dry 6 or 7 wings. Carefully lower wings into oil and fry, stirring occasionally, until cooked through, golden, and crisp, 5 to 8 minutes. With a slotted spoon transfer wings to paper towels to drain. Pat dry and fry remaining wings in same manner, returning oil to 380°F between batches.
In a large skillet melt butter over moderately low heat and stir in hot sauce, vinegar, Rosemary and salt to taste. Add fried wings and toss to coat.