These are scammers.  No sending fax number, just a removal phone number from the Kansas City (Johnson County) metro area, with the company name "R&D Seal Coating" - which company does not exist.  There is an "R&D Sealcoating" company in the state of Virginia - nowhere near Kansas City.

They want you to call the 913 area code number to get an estimate.  This number doesn't go to any business according to the Internet.

I have put this information on this website before.  They're doing something to get it removed.