My KPA500 kit that came about a week ago, came with 1/4" 4-40 screws for the Z bracket that should correct the popping. John N1JM -- View this message in context: http://elecraft.365791.n2.nabble.com/KPA-500-Heat-Expansion-Pop-tp7106945p7110484.html Sent from the Elecraft mailing list archive at Nabble.com.