For really tough stuff, stains marks smudges road tar bird debris and even fly droppings I have found that “Mr. Cleans Magic Eraser ” works very will. Then you remove the residue with mild soap and water. Funny that I havent seen any pro with logos on their boat or shirts from ” Pledge ” :-DPractice Angling CPRCatchPictureRelease2010 PIV 200SHO