oops, auto tranny pro help

[veltex]

the other day I went to change fluid and filter in my t400, decided to kit it while I was at it, just the heavy duty version nothing radical, any way, I have two pans one with most of the fluid and the other with some fluid, this is the one I laid the valve body in while I was getting everything else ready to go (it was very clean). Everything went back together fine, pushed pans and stuff to side to clean up later. Truck is out of the garage and running great, towing no less, cleaning up a couple days later I find a very small screen, like an in line type smaller than a pencil in diameter and about 3/4" long, the only place I figure it would fit is inside one of the governer tubes, it must have slipped out of body and into the fluid, I am running without it and dont think I want to take valve body back off, is it some sort of backup for big particals that get past filter? Anyone seen one of these? thanks