A fellow is going on a tour of a factory that produces various latex products.

At the first stop, he`s shown the machine that manufactures baby-bottle nipples.

The machine makes a loud hiss-pop! noise.

"The hiss is the rubber being injected into the mold," explains the guide.

"The popping sound is a needle poking a hole in the end of the nipple."
Later, the tour reaches the part of the factory where condoms are manufactured.

The machine makes a noise: `Hiss. Hiss. Hiss. Hiss-pop!`

"Wait a minute!" says the man taking the tour. "I understand what the `hiss, hiss,` is, but what`s that `pop!` every so often?"

"Oh, it`s just the same as in the baby-bottle nipple machine," says the guide. "It pokes a hole in every fourth condom."

"Well, that can`t be good for the condoms!"

"Yeah, but it`s great for the baby-bottle nipple business!"