Either corrosion resistant metal or a plastic. Something about the size of
a barbecue grill grating. But the grates could be narrow flatbar vertically
oriented. Looks like most barbecue grill grates are spaced almost 1/2",
that's too much spacing. Needs to be about 1/4" spacing. The porcelain
coated or affordable, the stainless steel are pricey.

Thanks.

Trying to make a cat litter box that separates the waste from the litter.
They can be purchased, but I want to make one.