Altima Antenna Removal?

I tried to remove the antenna off my 1996 Nissan Altima and got to the point where I needed to remove the round tip at the top of the antenna so I could slide it out. I wasn't able to take the tip off. Is there a special way to remove the tip? Does it screw off? IF so, is it Clockwise or counter Clockwise? Any suggestions are appreciated.

Thanks
Eddie