Hi Aaron & all Yes indeed, there is some stuff at:- http://website.lineone.net/~dave.cushman/excludertypes.html I corrected some spelling mistakes on it before posting this... I am doing an alphabetic clean up of web pages and have just reached the end of the "e"s. In the past I have come accross some Langstroth sized wire excluders that were too narrow to let any worker pass, but they were made in the 1940s in South Africa and we could be looking at racial difference rather than size difference in this case. Best Regards & 73s... Dave Cushman, G8MZY Beekeeping & Bee Breeding Website... http://website.lineone.net/~dave.cushman