Kitty, PLEASE Stay away from putting the perches that have the holes in them in the cage. My grey is the one that dblhelix was referring to. She had one of those perches in her cage, and did get her nail hooked in one of the holes and couldn't get it out. I was home, but in another room and each time I walked by her cage, I didn't notice. I thought she was playing as she sometimes yells at her toys and appears to be fighting with them. She had a toy hanging right near there. Finally when she didn't stop yelling at it, I saw she had her nail stuck way in there, it was very difficult to get her unstuck. I had to remove the perch with her on it, take it & her out of the cage, and try to maneuver her nail out. All the time, she was getting hysterical, flapping, and screaming!
It was very scary for both of us.
I just Thank God I was home, I have heard of birds that will chew their foot off if they get it stuck for too long of a time.
So, from now on, I use the perch on the outside of her cage ( she does love to use it) and I monitor her when she is on it.