For my bigger Dum's, I just crumple up newspaper and lay it around their cages. Most of the time I only see heads sticking ouf from underneath it. I put several pieces at each end of the cage. It's hard to find hides for the larger boas or pythons.

For my 2 small Dum's I use the hollowed out half logs by ZOO Med or T-Rex, plus I put some crumpled newspaper in their tubs also.

My cages are sparsely furnished, for ease of maintenance.

I found that when I used aspen bedding, my smaller Dum's would burrow under it also.

If you have a nicely decorated cage you could probably use some cork bark slabes and make your own custom sized hide.
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2.4 dumerils boas, 1.1 albino burmese python, 0.2 bearded dragons, 1.0 german giant bearded dragon & 0.0.1 sulcata tortoise