This guy is getting a tour of a latex factory (not Vandelay.)
The guide takes him past a machine that goes "Hisss-pop!" over and over. The guy says, "What's that noise?"
The guide says, "This machine is making baby bottle nipples. The hiss is the latex being inflated around the mold. The pop is a needle that puts a hole in the tip."
They go to another wing of the building and the guide says, "This machine is making condoms." As they stand there, the machine goes "Hiss, hiss, hiss, hiss, hiss-pop!" The guy says, "Wait a minute.." and the guide says, "I know what you're thinking. Yeah, the machine puts a little hole in the tip of every fifth condom."
The guy says, "Jesus!! Don't you lose sales on those things?"
The guide says, "We do, but it does wonders for our baby bottle division."