What is the thingie on the WBT Bananna Plug


I am looking at getting some bananna plugs, and in particular have noticed the WBT model 0645. It looks like it has an insulator or something plastic that protrudes from the front parallel to the bananna extrusion. Anyone know what this is? Looks like this will prevent the bananna portion from going into the receptacle, will it?

Also, any comments on this plug, where to get it, or other comparable connectors. Please, Bananna only because that is all my speakers will take, the have 4 bananna holes per speaker (no "spades are better" please because I can't use them).
Here is the wbt cite

http://www.wbtusa.com/wbt0645.html

Thanks in advance for your helpful comments and/or jokes!
south_park
The plastic on the WBT of course does not keep it from connecting to the speaker that would be counterproductive.

The WBT banana opens up once you install them into the speaker post and you turn them as tight as you desire.

It is an excellent product. I don't carry it but Synergistic offers it on their cables so I have them in here all the time.
Are you referring to the angled WBT bananas? I believe I have what you're referring to on my biwired Virtual Dynamics speaker cables. The protruding plastic pins seem to help with alignment and in my case, keep them right side up and prevent them from twisting during tightning. They actually fit snuggly on the other side of the banana plug and don't seem to hinder installation. If they are there for another use, I haven't figured it out and I'm using them incorrectly. Good luck.
Yes, I am referring to the angled plugs. See the situation is that my speakers have 4 flush holes in the center of the rear of the speaker for biwiring with bannanas, they do NOT have binding posts. So if that plastic dealie is designed to hit or engage the outer periphery of a binding post to prevent rotation of the plug, it will likely prevent the bananna from being inserted into my speakers, right? At least this is how it looks from the picture. Do you get what I am saying?