Thats also where the inspector likes to put the red tag when he finds a non approved piece of equipment.That way you can't say you didn't see it is a $5000 fine for pluging it in.The holes and nibs just give better mecanical resistance as not all mass produced plugs are the same.Hospital grade plugs are no different than spec grade(made on the same assembly line) they are just found to be "tighter" during inspection so they get a green dot.We actualy have a gauge made by hubble to test them with
cheers
[This message has been edited by frank (edited 12-04-2006).]
