Here is a letter from Roadsmith dated 12-2015 (It will download a PDF File)
https://www.google.com/url?sa=t&rct...TcMDjRWyaY8Dmw&bvm=bv.121421273,d.dmo&cad=rja
https://www.google.com/url?sa=t&rct...TcMDjRWyaY8Dmw&bvm=bv.121421273,d.dmo&cad=rja