I bought the foam inlay along with Thon 2U drawer for my wireless mics and IEM beltpacks. It works like a charm especially when you're touring and do not want stuff to rattle inside your rack and maybe break.
It's easy to make a layout for your mics or whatever you're gonna stick into the foam. Just place your item on the inlay, count how many pre-cut foam cubes you have to rip and voila! You have your custom drawer ready to protect your equipment during transport.
Tip: After you rip the pre-cut foam you can put it on the bottom of the drawer, so when you're placing your mic in the foam it doesn't get to the bottom side of the foam touching the drawer.