I'm using this adhesive to help bond and fill the gaps between some wooden battens and the metal structure of a VW Transporter. It's recommended on lots of Van/Motorhome sites and I can concur it really does the job very well. It takes a fair degree of pressure on the mastic gun to extrude the adhesive, but with a bore of 5mm+ it's not too bad. The resultant bond is very strong, but because the adhesive remains flexible, heat induced expansion in the metal does not damage the seal. Not cheap but very effective.