Transmission filter change gone wrong

[885.0conv]

So I went to do the first transmission filter change on the 95 mustang v6 I inherited besides the fact I dropped the pan and made a mess I found something extra in the fluid. Luckily I found it before I put the pan back on. I looked and could not figure out where it went. Also I assume the filter goes in the hole that is located on the front driver side under the tranny. I didn't see where it goes because the filter was in the pan when I dropped it. Here is a pic of the part I found in the fluid. Any help would be greatly appreciated.

 

[jrod2423]

Its a dust plug from the factory, it can be discarded as it was only used when the car was in production to keep dust and dirt out

 

[94GTCoupe]

Agreed, plug from the factory.
Go ahead and discard it.