The Viking Microfast® Quick Response Fusible Element Horizontal Sidewall Sprinkler VK307 is a small thermosensitive solder link spray sprinkler available with various finishes and temperature ratings to meet design requirements. For light hazard occupancies only. The special Polyester and Electroless Nickel PTFE (ENT) coatings can be used in decorative applications where colors are desired. In addition, the Electroless Nickel PTFE (ENT) coating has been investigated for installation in corrosive environments and is Listed/Approved as indicated in the Approval Chart(s).