I can't help with the DOT question, but Flaps are what protect the tube from chafing on the wheel. They protect the tube from rough spots and rust, so yes they should be used.
Mike B
Mike Boteler
1956 Chevy 3100 Resto Rod 1952 Willys M38 Army Jeep 1983 Jeep CJ7 Laredo 1984 Jeep CJ7 +++++ Silver Spring, MD
