Expired. Do not use expired silicone sealant. exhale as it may not heal properly. In the case of a fire protection product for buildings, failure to cure in the event of a fire could result in fire protection failure. Check the date code printed on the tube, it is in the format MMDDYY. (Search Google for data sheet 3mtm-fire-barrier-water-tight-sealant-3000-wt.pdf). Otherwise it would be a good product based on the specs, just make sure it's from the latest batch.