[Elecraft] K3- Part fell out!

[Dennis W1UE]

I dropped d a lock washer into the bowels of my K3 today, so had to invert
the unit to get the washer out of the unit.  When I did so, the washer fell
out of the unit, but so did another component.  Its a small rectangular
part, white on one side and blackish on the other, and either "3K3" or
"3R3" is stamped on it.  I don't know where the part came from, or where it
should go back' I'm just sure it doesn't belong sitting on my bookshelf
rather than be in the radio.

Can anyone maybe help me find where it should be going?  I know its not an
easy
thing to diagnose, but any suggestions on where it should go before I try
taking
the radio apart again.

Dennis w1UE