This item appears to be an IF filter for a Racal RA6790/GM HF radio receiver.  Markings are MODULE SPECIAL I.F. FILTER #4  455 KHZ 6.8 KHZ.  The physical condition is very good showing signs of ordinary use and there are no internal rattles.  Sold as pictured, untested, and AS IS and cannot be returned.  From a non-smoking home and shipping is $9.99 for USPS to 48 states.  Thanks for looking!