The outdoor enclosure, designated WPBB or WPLPBB, is a part of the SLP/HSLP Series. The enclosure is composed of premium Lexan material, which offers weather protection and permits the required full candela output. This extremely well-built enclosure satisfies many installation criteria, such as preventing moisture from getting inside the enclosures. The 4" mounting plate in the Outdoor Series has a Super-Slide feature that enables the installer to quickly test for supervision. The device also has a locking mechanism that fastens it to the bracket without exposing any screws. The proprietary Checkmate - Instant Voltage Verification capability, another feature of the HS-24, enables the installer to check the voltage drop draw and compare it to the blueprint. The HS-24 Series appliances are three years from the date of purchase and are listed for use with fire prevention systems under ANSI/UL 464 and ANSI/UL 1971.