TA Aerospace FASTBLOCK^® 301 type III is a two part addition cured low-density solvent-free aircraft firewall structure sealant/adhesive. FASTBLOCK^® 301 type III cures in room temperature to provide excellent thermal and fire barrier characteristics. The cured FASTBLOCK^® 301 is effective at temperatures from -65˚F to +400˚F (-54˚C to +204˚C) and is able to withstand temperatures of up to +2000˚F (+1093˚C) as per FAA AC 20-135.