First condom purchase

This young man walks into a drug store to purchase his first condom.
He goes up to the clerk, who happens to be a horny old woman, and asks rather shyly for a condom.
"What size would you like?" she askes back.
"Size?" he responded, "I didn't know they came in sizes."
"Sure. There are several sizes to choose from." she offered, "Why don't you go out into to the ally behind the store. You'll see a fence there with several holes in it about waist high. Get yourself excited and insert your member into the holes. When you find the one that fits, look at the number above the hole and come in and tell me what it is."
So the young man goes behind the store, finds the fence, sees the holes and begins to get himself excited.
Mean while the horny old woman runs to the other side of the fence.
As he inserts himself into the first hole she grabs him and masturbates him.
The young man is rather surprised. He moves to the next hole, inserts himself and the woman lifts her dress and places her rear to the fence.
Again the young man is amazed. He moves to the third hole, inserts himself and the woman gives him oral sex.
Finally, he puts his member away and proceeds back into the store.
The clerk also rearranges herself and rushes into the store.

The young man goes up to her and she says, "Well what size condom do you need?"
"Condom?" he replies, "The hell with the condom. How much for three feet of that fence?"