Hi All; I have for sale a real nice 400hz CW Filter. Tested fine in SB-303. Pics: http://www.myradioroom.com/heath400hz1.jpg http://www.myradioroom.com/heath400hz2.jpg Price is $45.00ppd( was $50ppd.) This is super fair so such a clean one. Tnx & 73.. Rich WA2RQY