Interestingly enough, I just received KPA500 #594 and there is an errata sheet with 1/4" 4-40 screws attached. John N1JM -- View this message in context: http://elecraft.365791.n2.nabble.com/KPA500-Heat-Expansion-Pop-tp7093999p7103028.html Sent from the Elecraft mailing list archive at Nabble.com.