These gauges are designed to fit into either our inline regulator or our blowtie units.  These can be used for water or gas.  
 
Specifications
Pressure: 0-150psi (0-10bar)
Graduations: PSI + Bar
Material: Brass/Plastic/Copper Capillary
Gauge Diameter: 20mm
Probe Diameter: 7.8mm (designed to fit 8mm hole)
Accuracy: These gauges are accurate to 10% of the whole pressure range.  (ie the 0-30psi Gauge is accurate to +/- 3psi).  For more accurate gauges we recommend the larger 50mm gauges that we sell.
 
WARNING:
Do not exceed gauge pressure.  If you exceed gauge pressure it will damage the capillary in the gauge and prevent the gauge from working correctly.  NEVER exceed the maximum gauge display pressure range.
Not tested or approved for pure oxygen.
 
We stock a range of these different pressure gauges.
 
These are quite easy to install into a tank and depending on the thickness of the tank wall all you need to do to fit a Gauge like this is drill a hole in the tank about 8mm in diameter then insert the gauge and secure with screws.
We have several different models available in different pressure ratings:
KL14984 - Mini Gauge 0-15psi
KL14991 - Mini Gauge 0-30psi
KL15004 - Mini Gauge 0-60psi
KL15011 - Mini Gauge 0-150psi
KegLand does not stock the 0-23psi gauges anymore. It has been replaced with the 0-15psi