My dad loves to watch the bees when he has free time so it made sense to put an observation window into a hive box. We took a medium and pretty much just cut out a square portion. Then from inside installed a clear acrylic as the window to prevent bees from flying out when we lower the piece we cut out. We added the super with the observation window as the number 3 box on the Mountain View Hive as the colony was booming and should be running out of space just about now due to a good Winter flow.
Here’s an eight second video