Securing Stacking Shelves to Cage

[1lila1]

I finally found some of those stacking shelves at the dollar store.  They'll make the coolest little rattie bunk beds I think.  I'm just not sure how to secure them to the cage. I thought about zip ties but don't want to have to poke holes in the shelves.  I'm at a loss.   Any ideas? 

[twistedlittle-puppy]

petsmart sells these little clips that you stick onto a litterpan and then clip onto the wire bars to keep them in place. they worked pretty well for me, though they're kinda annoying to clip/unclip every time

[ratsamongus]

I have never tried it, but what about velcro?

[Kendra]

I tried just setting mine in, then I tried to tie it down with yarn, but, in the end, I finally just poked the holes and zip-tied.  Nothing else would keep them up.