Smokin' Nuns

Two nuns were in back of the convent smoking cigarettes, when one said: "It's bad enough that we have to sneak out here to smoke, but it really is a problem getting rid of the cigarette butts so that Mother Superior doesn't find them."
The second nun said: "I've found a marvellous invention called the condom, which works really well for this problem. You just open the packet up, take out the condom, and put the cigarette butt in, roll it up, and dispose of it all later!"
The first nun was quite impressed and asked where she could find them.
"You get them at the drug store, sister, just go and ask the pharmacist for them."
The next day the good sister went to the drug store and walked up to the counter. "Good morning sister," said the pharmacist. "What can I do for you today?"
"I'd like some condoms please" said the nun.
The pharmacist was a little taken aback, but recovered soon enough and asked: "How many boxes would you like - there are twelve to a box."
"I'll take six boxes," said the nun. "That should last about a week!"
The pharmacist was truly flabbergasted by this time, and was almost afraid to ask any more questions, but his professionalism prevailed. "Sister, what size condoms would you like? We have large, extra large, and big liar size."
The sister thought for a minute, and finally said: "I'm not certain, perhaps you could recommend a good size for a Camel?"