Drop-In Thread Anchor Dust Plug

I installed some drop-in threaded anchors in the floor of my garage, but wanted a way to keep dirt/junk out of the threads when the anchors are not being used. 

I modeled these up to thread into the anchor. The low profile plug prevents stubbing your toe on it and the hex drive allows you to install remove with an allen key.

I haven't tested the ½-13 or the ¼-20 plugs, as I only have the 3/8-16 anchors installed in my floor. If you try out the ¼ or ½ sizes, give me feedback on how they work.