(Can be used in conjunction with the SHOWERMI$ER family of products.)

Ever wondered, “Have I got enough water to stay another one or two days?”.  When dry camping (Boondocking), we all know the importance of keeping track of exactly how much water is left in your tanks. Our new H2F-FM Water Tank Gauge now features a larger backlit screen that actually shows the number of gallons (or litres) remaining in your tank, rather than the traditional full/half/empty display.  This makes it easy to know your average daily water usage and to help plan your next adventure. The good news is the sender is fitted in the hose line and there is nothing fitted to the tank.

We now have two exclusive RV & marine models, one suited more to the DIY aftermarket H2F-FM and our new Bluetooth  H2F-BT12 . The perfect solution for tankless water systems! 

We now have two exclusive RV & marine models, one suited more to the DIY aftermarket flush mount H2F-FM and our new H2F-BT12 Bluetooth
Breakthrough Design for the RV and Marine Industries
*Takes all the guess work out of your water supply.
*Displays number of gallons left in your water tank.
*Counts down gallon by gallon from a preset amount.
*Stop wasting fuel by filling up unnecessarily.
*Know how much is used for washing, showers etc.
*Know your daily water usage in gallons
*Essential for bush/ free camping.
*Fitted in water line, nothing is fitted to water tanks.
*One unit can be used for any number or size tanks.
​*Displays in gallons or litres.
*It can be used in conjunction with your current system to accurately know your capacity and usage.
N.B. Does not include hose connectors, see Connecting Sender Unit below.
Our new RV senders and electronics are compatible with all commonly available RV and marine water pumps and will even work with gravity fed systems.


H2F-FM        $135.95 
Flush Mount
New larger backlit screen
12 volt DC
Suitable for marine & RV applications
Flush bulkhead mounting
1.4 Mt Sender Lead.*

Displays in gallons or litres.
​Sender extension leads available.

*Sender leads can not be cut and joined,
​extension leads must be used.

H2F-BT12           $139.95 
Use with Phone App

Bluetooh to your Phone
Suitable for Marine & RV applications.
Very easy installation.
Displays in gallons or litres.

*12 Volt Adapter for Bluetooth H2F-BT12 module is not included

​Sender extension leads available.

H2F-EX-3          $19.95 
Extensions (3 METERS EACH).

Model comparison:  
Larger Screen     
Sender Lead
Ext Lead Option
All applications 
​Display GAL or Litres
12 Volt only
Recessed Mount
1.4 Meters
AA Batteries or 12 Volt
Phone App (Phone Display)
1.4 Meters

 For information call 714-485-5904


Fitting recessed display 

The LCD Polarised Display on this new model is designed to be only visible when viewed from horizontal and below .
When viewed from this angle the display is extremely clear.
Using the display as a template mark out hole and cut to suit.
Fix in position with bolts provided or suitable screws..

Connecting Sender Unit
The display comes pre-wired with an approximately 1.4m sender cable. Extra 1.4m extension leads are available for the three pin plugs, up to 6 leads may be joined to make 9.8m in total length.  Leads cannot be cut and joined, doing so will void warranty, No Exceptions.
The thread specifications of the sender unit are 1/2″ BSP male.   Make sure the sender is fitted with the water flow in the direction of the arrow.
You will need to purchase two 1/2″ BSP female connectors to the size hose you have, usually 1/2″ or 3/4″ and two clamps.  “John Guest quick connections” also have fittings to suit their hose and the 1/2″ BSP sender unit.

Connection to 12 Volt DC
​It is recommended that you get the 12v power from the pump circuit.
Simply cut off the two pin 12v plug to the required length and connect the black wire to the negative terminal and the red wire to the positive power source.  All settings and amounts will be memorised if power is disconnected.
Current use at 12v:
8mA with the backlight LED on, Only stays on for 10 Sec.
3mA with the backlight LED off, goes to sleep 10 sec after flow stops.
8 micro amps when asleep.  (1,000 micro amps=1 mAmp) (1,000 mAmps= 1 Amp)

Programming Monitoring Capacity
Press “DISPLAY” button to turn display on, then press the “PROG” button, “ProG” will blink on the LCD display. Press and release “RESET” button to choose the value of the right digit.  Once the value has been chosen, press “PROG” button to save the value, it will then go to the next digit.  Repeat the above procedure to program the values for the five digits from right to left.
The maximum monitoring capacity is 99,999 litres.  The first time the meter is used fill the water tank and then use normally until empty.  Then note how many usable litres the tank holds and reset the meter accordingly.
*If there is no input for one minute during the programming procedure, the programming procedure will be terminated and goes back to the original status.

The TOPARGEE H2Flow will automatically turn on and display the litres remaining when there is water flowing through the sensor e.g. a tap is turned on.  It will automatically turn off 10 seconds after there is no water flowing.
To manually check remaining litres, press and release “Display” button and remaining litres will be displayed for 10 sec.

End of Capacity Alert
The TOPARGEE H2Flow will give an audible alert and the digits blink on the LCD display when the remaining capacity reaches zero or minus.

When the water tank has been refilled.  Press “DISPLAY” button to turn display on, then press the “RESET” button for five seconds, the “rESEt” on the LCD display blinks twice and the buzzer will sound, the unit will then be reset to the originally programmed value.  TIP!  You may find it easier to use the side of your fingernail or coin etc. to hold the button in for the five seconds.

Note: Due to continuous product improvement, specifications are subject to change without notice. For more general information or installation enquiries please refer to your supplier or website

To change from litres to gallons or gallons to litres:

  1. Disconnect the power (or batteries)
  2. Press and hold the “PROG” button while reconnecting the power.
  3. Release the button when you hear the long beep.  The display will be switched (from litres to gal, or gal to litres)
  4. Wait until the screen turns off and the unit will memorize the setting.​​