Where do you get that white grating?

[JAMills]

I have found it in both Lowes and HomeDepot

got mine at home depot but ask about the light dis fussers not seen them at my lowes but then again i astill wrking off the orginal piece i got. thebest way to cut it is with an iron mine wanted to breaking in sections for me (just burn it outside.)

As for cutting...
I use a large pair of D y k e s (Wire cutters, it censored the name) and just snipp one at a time. The first time is a little slow but once you get the rhythm it is pretty fast...LOL