Viking's Model VK638 Quick Response Extended Coverage Horizontal Sidewall Sprinkler is designed specifically to protect corridors, hallways, decks, walkways, and any other application where a wide spray pattern is optimal. The VK638 is cULus Listed for Light Hazard occupancies and has a K-factor of 8.0 (115).  The VK638 uses Viking’s patented flow-shaper technology to provide larger coverage areas at lower flow and pressure requirements. The sprinkler is cULus Listed for 28 x 12 ft (8,5 x 3,7 m) and 28 x 14 ft (8,5 x 4,3 m) coverage areas, with the deflector installed up to 12 in (305 mm) below the ceiling. The 28 x 12 ft (8,5 x 3,7 m) coverage area is unique in the industry, providing a significant flow and pressure advantage for fire sprinkler systems where this area of coverage can be applied. Available in 135°F (57°C), 155°F (68°C), 175°F (79°C), and 200°F (93°C) temperature ratings. The VK638 has a ¾ inch (20 mm) thread size, and is available in standard finishes that include brass, white, chrome, and black as well as a nearly unlimited variety of custom colors.