The GHSLF is a high quality, low profile, low frequency audible and visible appliance that offers a dependable audible and visual alarm. The GHSLF is ideal for any occupancy that requires notification appliances. The GHSLF horn offers a 520 Hz square wave, temporal 3 tone. A jumper selection is available for normal or loud decibel tone. A temporal 4 pattern is available when used with the Gentex GTSM Synchronization Control Module. The GHSLF is available in a fixed 15, 110 and 177 candela strobe. The GHSLF is shipped with a standard 4" metal mounting plate which incorporates the popular Super-Slide® feature that allows the installer to easily test for supervision. The product also features a locking mechanism which secures the product to the bracket without any screws showing. The GHSLF also features the patented Checkmate® - Instant Voltage Verification feature which allows the installer to check the voltage drop and match it to the blueprint. The GHSLF is listed to ANSI/UL 1971, ANSI/UL 464, CAN/ULC S525 and CAN/ULC S526, and is listed for use with fire protective systems and is warranted for three years from date of purchase.Standard Features Nominal voltage 24 VDC Unit Dimensions: 6-1/2" (16.5 cm) high × 5-1/2" (14.0 cm) wide × 2" (5.0 cm) deep Produces a 520 Hz square wave, temporal 3 tone Fixed candela options: 15, 110 and 177 Jumper selection for normal or loud dBA Super-Slide® Bracket - Ease of Supervision Testing Checkmate® - Instant Voltage Verification Prewire entire system, install mounting bracket, then install signals Input terminals accept 12 to 18 AWG Synchronize horn/strobe with Gentex GTSM Synchronization Control Module Temporal 4 pattern available when used with Gentex GTSM Synchronization Module Temporal 4 520 Hz measured per ANSI/UL 2075 Tamperproof re-entrant style grill and locking screw (optional use) Faceplate available in red or off-white Wall mount