I bought this Snake River monitor, model 703-Smart 3 Tank.
https://tankedge.com/products.html Similar (or possibly identical) to SCAD. I monitor fuel, holding, and water. The water uses a custom internal sensor, which I had to drill a 1" hole on the top of the tank. The fuel and holding use the external, stick-on sensor.
Similar but not identical. Snake River went out of business about 10 years ago...a company in AL bought their remaining inventory...they didn't last long though. TechEdge seems to be the latest owner of the SR trade name and are making their own versions of it along with their own brand name.
SCAD is actually a private label brand name for the Profile Tank Monitors, made by Ferriello Sales.
Profile Tank Monitors Dennis Ferriello was the National Sales Manager for Snake River for a number of years, left them when the quality of of Snake River products seriously deteriorated (some of you may remember when Hunter was installing Snake River systems had so many problems with 'em that they discontinued 'em fairly quickly) and started his own company making top quality tank level systems...in fact,replaced a lot of the bad Snakes River components on Hunters for owners. SCAD began private labeling them 5-6 years ago...they concentrate on the retail market, Dennis now does mostly OEM sales to boat and RV mfrs, putting their own names on the panels.
If your water tank sender is internal, I suspect it's a metal tank...your waste and fuel are either fiberglass or PE...'cuz the external senders will work on all materials EXCEPT metal.