The SKHEAT and SKPHOTO SK Series ADDRESSABLE SMOKE and HEAT DETECTORS are designed for both performance and aesthetics. SKPHOTO SK Series smoke detectors have a new modern, sleek contemporary design. Enhanced optical sensing chamber are engineered to sense smoke produced by a wide range of combustion sources (in accordance with more stringent code standards). SKHEAT SK Series heat detectors us state-of-the-art technology for fast response.