This is a remix of Emmett's "Preassembled Iris Box" without the knife edge spiked base.
See his here: https://www.thingiverse.com/thing:1811143
I suggest following his instruction as well. I used a break-off blade to get in between the layers, and I found that to work really well. You'll just have to be careful not to break off the blade inside the box, because it's a pain to get out.
12/21/17 Update: Spelled Emmett's name right.
3/18/18 Update: I put the STL file through the netfab stl fixer. Hopefully this corrects the issue some people are having with the mesh errors.