Help installing motherboard

[DougEFresh]

So I'm trying to install a new motherboard I bought into this case but something perplexes me. I put the standoffs in but there is this peg coming out from the case where I would want to put a screw in for the motherboard. It looks like a standoff but will not come off and it's solid with no screw lines. The case is a HEC 6C60BS Black / Silver Steel ATX Mid Tower. Can anyone tell me what this is and what it is for?

 

[DougEFresh]

See:

http://www.newegg.com/Product/ImageGallery.aspx?CurImage=11-121-037-S07&ISList=11-121-037-S01%2c11-121-037-S02%2c11-121-037-S03%2c11-121-037-S04%2c11-121-037-S05%2c11-121-037-S06%2c11-121-037-S07%2c11-121-037-S08%2c11-121-037-S09%2c11-121-037-S10%2c11-121-037-S11&S7ImageFlag=1&Item=N82E16811121037&Depa=0&WaterMark=1&Description=HEC%206C60BS%20Black%20%2f%20Silver%20Steel%20ATX%20Mid%20Tower%20Computer%20Case