Two guys both have 9:00 a.m. appointments at a vasectomy clinic.
So, a nurse greets them and tells them she has to prep them for
surgery and takes them to a private room.  She tells the first 
guy to take off his clothes and sit on the exam table, which he
does.  She then takes  his manhood in one hand, and begins to 
masturbate him.

He says, "Whoa!   What's going on?"

She replies that it is all standard procedure, and  that she
has to ensure that he has no blockages. The guy thinks, "How
bad can it be?  So he agrees and allows the nurse to complete 
her task. Once done, the nurse tells him to go sit down, and 
repeats the Instructions to the second guy.  When he is up on 
the exam table, the nurse gets a big smile on her face, licks 
her lips, and begins to perform fallatio on him.

  The first guy says "Hey,  what's this?  I get jerked off, and
he gets a blow job.  That's not  fair."

  The nurse looks up at the first guy and says, "Sorry buddy,
that's the difference between Blue Cross and HMO!"