I ordered 4-1/2 gallon jugs of woodboiler solution, when filling out the order form I came to a line that asked for discount code. I did not have any discount code so I entered " Military veteran". When I entered all the information required it came back invalid code. No problem, went ahead and completed order. When my order arrived I noticed there were 5 jugs. I checked the invoice and found the following note. (Plus 1 free- THANKS FOR SERVING OUR GREAT COUNTRY). This was totally unexpected. I took a picture of the invoice and put it on Facebook, I hope everyone needing woodboiler chemicals will see it and send there business to this great company. I wish there was a way to put this directly on woodboiler solutions llc's page. Thank you so much. PROUD VETERAN!!!