This log rock wool will replace your old or worn log rock wool and restore the looks of your gas fire, your ceramic logs and ember bed, This log rock wool will work natural gas or propane gas ceramic fiber log sets, It is the rock wool that make gives your ember glow their look, This Replacement Gas Log Rock Wool is made by Rutland Log Bright and will work with perfect compatibility with other Rutland fireplace components, Creates realistic ""glowing embers"" for gas fireplaces, Suitable for use with natural gas and propane log sets, SKU: RTLD310