Rochester Gauges Spiral Gauge.  Tank depth should be at least 1/2” greater than the length of the gauge.   The additional depth may be considered "reserve" at the bottom of the tank that will not be measured.  
- Designed for top mount
 
- Direct-read dial comes standard.  TwinSite sender dials available in 240-30, 0-90 or 0-30 Ohms also available, contact us for assistance ordering them.
 
- 1-1/2” MNPT tank connection
 
- Suitable for up to 25 psig maximum
 
- UL Listed for flammable liquids when gauge is 36” or less