Zilla slimline desert 50 compressor

[momohobobobo]

so i have the zilla slimline fixture and bulb, and i was wondering what that little compressor thing is and what its for? its like a little capsule that can be removed. And when i turn on the bulb a little light in it flickers purple until the bulb fully turns on. It just doesn't make sense to me because people say that you can use regular fluorescent fixtures for uvb bulbs, but i dont think regular fixtures have this compressor thing. So it makes me wonder maybe the compressor thing is a way to manufacture the zilla slimline fixtures for cheaper or something... idk. If anyone knows i'd love to hear why, its bothering me :?

oh, and im going to get the reptisun 10.0 hopefully by the end of this week, would the reptisun fit this fixture?

Thanks