Tool - Foam Gun
GOCHANGE Foaming Gun Pu Expanding Foam Gun Caulking Gun Metal Body Pro Heavy Duty PU Foam Gun Grade Expanding Spray Application Applicator
Great Stuff 230409 Pro 14 Foam Dispensing Gun
Another less expensive but still ok gun is...
http://smile.amazon.com/gp/product/B0026HEZRO?psc=1&redirect=true&ref_=od_aui_detailpages00 $23 + $7 shipping
I use three different types of foam depending on how much expansion
No expansion - Foam Adhesive
Small expansion - Foam Windows and Doors
Large expansion (and fire seal) - Foam Gap Filler and Fire Seal
You also need Foam Gun Cleaner .
Use cleaner on the foam gun after you finish. If you plan to use the gun the next day then it is ok to leave it overnight with the valve closed and the gun vertical with a non-empty can on top.
In damp weather you need to be quick because the foam sets very quickly in the damp.