I absolutely must have Primus' Omega-lock. I also need the back plate for the Planet mode. The open space the missing piece leaves can be seen here: It can also be identified as Primus' BUTT FLAP in Robot mode. I only do business through PayPal. If you have what I'm looking for, please shoot me a PM with a price. I am available from 9 AM to 5 PM, Monday through Friday. These would be the best times to contact me. My feedback can be found here: http://www.tfw2005.com/boards/junkion-exchange-feedback/318594-robticon.html Thanks for looking!