Just wanted to add that the Pierco medium frames have larger, drone-sized, cells. This put an end to my thinking about using 3 mediums for the broodnest ... Waldemar LI, NY Hi Maurice I have measured several samples of Pierco one-piece frames and there are two possibilities as examples exist in both 5.20 mm and 5.25 mm depending on which die was used for production. I cannot find any numbers on the finished frames that refer to the die, so you will need to measure 20 cells to establish which size you have. :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and other info --- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::