Currently we use the trays for collection (for chicken and duck eggs -- we like that these hold larger eggs). My initial reason for purchasing them was to use them inside of a square container into which I would build an immersion washer. Unfortunately, the containers that I found to use for the purpose were just a little bit too small to hold the trays, so we're still washing by hand, and the trays are just a means of collection from the coop. I'm still looking for a 15" x 15" square plastic bucket or tank i can lower the full trays into for automated washing. Thes will work in the meantime