We do not carry products that are labeled to kill squirrels. We do carry Tomahawk Professional Excluder Model E50D as well as other traps that work great for squirrels. If you know where the squirrels are entering you can use a Squirrel Trap. Also, try and seal up any entry points using copper mesh. Please see our Squirrel Page for more information.
We do have one way door excluders which allow the squirrels to leave the attic but not reenter using the same hole that would be a great option to try out. It is very important to seal up every hole possible to keep the squirrels out for good. You have to find where the squirrels are getting into the attic and close up the entry points. That is the only option for future squirrel free living.