Cover plates for net cups/plugs in hydroponic systems. I made them for my BerlinGreen/GreenBox.

Comes in two variants both are 49mm in diameter and 2.2mm high (freely adjustable):

• Blank - fully covers an empty net cup to block light and prevent algae growth
• Seedling - same cover with a cutout to allow a seedling or stem to grow through

Useful for systems where not all slots are in use, or during the early stages of a grow when you want to keep unused positions covered.