The diameter of the required hole isn't very clear if it's contained in the instructions. I didn't measure properly and had to come up with a solution which is less than desireable. I'm sorry I don't have the dimension to share here. I was reviewing another product and was reminded of my challenge with this install. After cutting a circle in plexiglass .25" larger than the required. I was able to cut the proper hole size within that and provide a good mounting surface.Haven't used them much yet. Put them in an RV counter top and run to an independant circuit. They look good and I don't doubt they'll do the job.
UL Listed Light Socket Polarized 2 Prong To 3 Prong Outlet Adapter W. Safety Seal Grounding Plug Converter + Waterproof Outdoor Extension Cord Plug Cover For Electrical Outlets
30 Review
SYCON 3 Way Wall Outlet Extender AC Adapter, 2-Prong Swivel Mini Indoor Wall Tap Power Outlet Extender Plug, White
39 Review
Green 50Ft Indoor/Outdoor Extension Cord - 3-Prong, 13Amp, 1625W, 125V - Amazon Basics
37 Review
Kungfuking Desk Power Grommet Outlet Strip With 2-Socket &2-USB Ports, 9.85 FT Extension Cord, ETL Listed
38 Review
Robertson Worldwide ISL432T8HEMV AH 3P20160 120-277V 50-60Hz High Power Factor 4 F32T8 Linear Lamp Fluorescent eBallast
6 Review
💡 Hydrofarm Quantum QT400 Dimmable Ballast for 400W Grow Lights
5 Review
Fulham WorkHorse WH2-120-C Adaptable Ballast - 2 Pack
3 Review
💡 Electronic FL Ballast ICN-4P32-N (Formerly ICN-4P32-SC) for 3-4 F32T8 F40T8 F17T8 Lamps, 120V/277V Compatibility
5 Review