Self-leveling, ready-to-use, single component, neutral cure, elastomeric silicone firestop that also acts as a barrier to water leakage and airborne sound transmission. For use in horizontal applications. Provides up to 3-hour fire protection. Light gray color, no mixing required. When properly installed, product provides up to 3-hour protection against the spread of fire, smoke and noxious gas in tested and listed systems. 3M Fire Barrier Water Tight Sealant 1003 SL meets UL Water Leakage Test, W Rating - Class 1 requirements for systems tested and listed in accordance with ANSI/UL 1479, provides acoustic benefits by minimizing noise transfer (STC-Rating of 56 when tested in a STC 56-rated wall assembly) and acts as a smoke seal for installations requiring the optional L-Rating. Meets the intent of LEED VOC environmental regulations, meets International Building Code (IBC) and other key life safety building code requirements.