How about a dumb question

Just got back into bow hunting this year.Got injured at work several years ago, almost cut my right hand off.I shoot a bow lefty.My old bow is a bear Whitetail II ( that tells how long I've been out)This year I felt like I could reliably shoot again got enough strength back in my hand to have the confidence to shoot .So I bought a 2007 Bowtech Allegiance. Man I love that thing.My question dumb as it may sound is on the cable guide there ia a little square looking box that holds the cables where they cross I understand the purpose of this What I don't understand is there is a small gold looking plate on the top of this little box that will move from side to side.When you move it enough a little green light comes on .What in wide world of sports is this contraption for?This little gizzmo has got me befuddled......Thanks

Is this it?

http://www.cabelas.com/prod-1/0039181417439a.shtml

If so, then it's supposed to come on to show you, the hunter/archer, that you've reached a predetermined draw length, or possibly indicate string stretch. Most new bows have a draw stop on the cam that you should pull to each time, provided the draw length of the bow is the correct draw length for you. That should be all the indicator you need, a good solid wall.

A good string will come prestretched, also eliminating the need for this.

I'm glad you asked this question. I've never seen one of these before.

Yep,That's it.I have yet to see the light come on,But I can move it around with my finger and light it up.It could be I am concentrating more on the peep than the guide.Thats the first one I have seen also.Thanks for the reply.

A Creeper Peeper.. haven't seen one in a while. We used to sell them