Re: Bismarck ringed python
A 4' cage should be fine. Remember to cover up most of the lid/screen though. Ringed Pythons are a thin skinned species, and come with shedding problems if humidity isn't kept right ;)
The best cages I've used were Animal plastics. Look into getting your new Ringed Python a T-10...Well worth the money!
Re: Bismarck ringed python
They are on sale too! With those cages...are the swinging doors or sliding ones better? And do you use substrate with those? It seems like I see lots of snakes in cages like this without substrate, is that for show purpose or what?