Little Johnny, Toothbrush Salesman

little Johnny's riding in his dad's truck. looking in the glove box, he sees a pack of condoms.
"Dad, what are these for?"
his dad replies "Son, those are for smoking. now put them back and close the glove box."

later that week Johnny and his friends decide to try smoking.
Jimmy sneaks some cigarrettes from his house, and Johnny stops at the local drug store before meeting Jimmy at the tree house.

he asks the Pharmacist for a pack of trojans. the Pharmacist raises an eyebrow thinking Johnny is a bit young for this. but, in his proper customer service voice he asks
"What size?"

Johnny smiles "big enough to fit a Camel" :D