ELECRAFT K3 and K3S 250HZ CW and DATA Filter -  KFL3A-250 - PERFECT CONDITION
 
If you want to add a CW filter to your K3 or K3S,this could be for you.
Pretty simple to install.
These were  $169.99 on the Elecraft site before they discontinued them.
Buy it here for less :)
I will be listing Elecraft option boards and K3 radios very soon !

Please see pictures of everything included.

I can be reached through QRZ if you have questions about this unit.
Larry K6RO