FIELD CONTROLS SSK-1 & SSK-2 Spillage Safety Kit is a device designed to detect flue gas spillage from a blocked flue system and/or inadequate draft. It is typically installed on L.P. and Natural Gas-fired systems with draft hoods. The kit includes two enclosed spillage sensing switches with manual reset, jacketed lead wire, jumper wire, self-drilling sheet metal screws, and adhesive tabs. The switches are mounted on the draft hood and connected in series into one side of the thermostat circuit. If flue gas spillage is detected, the switches will shut off the gas supply to the appliance.