Commercial & Residential use. Two Separate Valves with Adjustable Closing & Latching Speed. Universal Application, Non handed (Suit for Both Right & Left Hand Door). Designed for All Standard Installations. Factory tested to Meet or Exceed ANSI Standard 156.4 5 Years Guarantee. Power Size Ranage can be ed 1 to 5 Optional Back-Check (703BC,704BC,705BC) Controlled by Separate Regulation Valve