This is the RDS 18 inch Rochester Visual Fuel Gauge. These are mechanical fuel gauges. The tank gauge should be 1 inch shorter than the depth of your tank!
We offer fuel gauges ranging in size from 4 inches to 26 inches.
This gauge is used on RDS Model 71783, 71790, 71791, 71792, 71793, 71083, 71083PC tanks.