Prevent the spread of flames, toxic gases, smoke, and water with these fire barrier insulation pads. Measuring 7" x 7" x 1/8" thick, these firestop block pads are perfect for use with metallic or non-metallic outlet boxes, metal electrical cabinets, mechanical cabinets, and electrical boxes, and intumesce and expand at 20 degrees F (104 degrees C) to form an insulating char. Each outlet putty pad is easy to apply by hand and does not require any mixing. Fire barrier moldable putty pads do no contain any asbestos fillers or volatile solvents, and each fire barrier putty pad is is rated for up to 3 hours as tested in accordance with ASTM E814, UL 1479 and ULC/CAN4-S115-M test standards. The putty pads for electrical boxes are not to be exposed to water, heavy moisture, freezing temperatures, or hot temperatures above 120 degrees F (49 degrees C). If freezing occurs, thaw fire starter putty out before use, and keep each intumescent firestop dry and stored in original container. Holdrite HydroFlame offers a limited 2 year warranty on all firestop insulation products free from defects in material and workmanship.