SpecSeal® SSM Firestop Mortar is a lightweight, cost‑effective firestop mortar engineered to seal oversized openings in concrete walls and floors. When mixed with water, SSM Mortar creates a low‑density, easy‑to‑apply slurry that spreads smoothly into penetrations, delivering fast, efficient installation across a wide range of firestopping applications. Once cured, SpecSeal SSM Firestop Mortar forms a durable, non‑shrinking seal that resists spalling, cracking, and damage from freezing or temperature fluctuations. Its stable composition ensures long‑term performance and reliable protection against the passage of fire, smoke, and hot gases in commercial, industrial, and institutional environments. Ideal for mechanical, electrical, and mixed‑use penetrations, SSM Firestop Mortar provides a clean, high‑performance solution for restoring fire‑rated integrity in large or irregularly shaped openings in concrete assemblies.