"I'm not sure why the other reviewer said that the top doesn't unscrew. You just have to take out 4 screws around the rim and rotate the tabs to remove the wire guard.
I like this because it keeps the bulb out of reach from my iguanas. I have 3 of these, and I am using Mega-Ray bulbs in them which are rather large, and protrude a bit, but the cage it still big enough. I love how the neck bends, because I have to attach the clamb in odd positions on the enclosures, and this makes me able to do so. I would recommend these to anyone."