Holds a tube of 310ml or 400ml caulk cartridge for sealing up gaps and cracks in the home. Provides precision and accuracy when sealing and filling in gaps load your sealant, and the gun will direct it to where you need it. Comfortable grip handle makes for easy use over long sessions. Quick release trigger and a built in hanging hook, this Professional Caulking Gun is easy to use and store when not in use.