The idea of using plant pot rims was suggested by Arthur Johnson.
The technique of using such rims was developed by Albert Knight and Arthur Johnson for postal transmission of breeding material.
I have merely expanded upon it to include a method of "transplanting" desirable drones into colonies that might otherwise have produced poorer quality drones.
The method uses rim sections cut from inexpensive 3" plastic flower pots. Two different types of flowerpot are used so that the rim from one will sit neatly inside the rim of the other type.
This method is simple to implement and costs very little, it provides a reliable method of transportation of honey bee eggs of either sex. Bee improvement enthusiasts, can utilise this method to raise queens or drones from selected colonies many miles away, but the raising process occurs within hives in easy reach in your own apiaries.
There is a possible downside to this process, but so far I have not seen it happen... It is possible that a colony may eat the eggs of a 'foreign' queen. The risk if this becomes greater as the racial difference between the introduced eggs and the raising colony becomes wider, but as most bee improvement programs are based on line breeding this element of bee behaviour is not very likely to become much of a nuisance... Indeed if it should occur, it can be considered a pointer to examine the racial purity of the colonies of bees concerned at both ends of the transport system.