True Fit Tank Fittings
  • Prior to installation, refer to Tank manufacturers recommendations before drilling outlet in tank wall.
  • All pipe work must be adequately supported.
  • Use a thread sealant on all threaded connections. We recommend Loctite 5331.
  • If you are using chemicals or have any special requirements that you wish to use your Tank Fittings in, go to the Tank Fitting Chemical Resistance Page or don’t hesitate to email us.
  • Please refer below for Minimum Recommended Hole Sizes.
  • Check the sealing surface to ensure it is free from debris and/or scratches which could cause leakage.
  • To obtain proper washer compression for fitting installation ensure the face of the washers fully contacts the tank wall.
  • Tighten the nut to ensure a water tight seal. We recommend Loctite 5331.
  • Hansen Tank Fitting can be used in conjunction with metal fittings.
15mm = 22mm or 7/8" Hole Saw
20mm = 27mm or 1 1/16" Hole Saw
25mm = 34mm or 1 3/8" Hole Saw
32mm = 42mm or 1 5/8" Hole Saw
40mm = 48mm or 1 7/8" Hole Saw
50mm = 60mm or 2 3/8" Hole Saw
80mm = 95mm or 3 3/4" Hole Saw
100mm = 121mm
or 4 3/4" Hole Saw

Hole Size for 15mm = 22mm
Hole Size for 20mm = 27mm
Hole Size for 25mm = 34mm
Hole Size for 32mm = 42mm
Hole Size for 40mm = 48mm
Hole Size for 50mm = 60mm
Hole Size for 80mm = 95mm
Hole Size for 100mm = 121mm


Remove the Back Nut and the Low Density Poly Washer (the firmer of the 2 washers) from the Tank Fitting Body. Slide the Tank Fitting Body through the hole in the tank. The Rubber Washer must be between the Fitting Body Flange and the tank wall (ensure the ribs on the Rubber Washer are sealing against the tank wall).


On the inside of the tank wall, slide the Low Density Poly Washer back onto the Tank Fitting Body and then wind on the Back Nut.


Tighten the Back Nut so that the face of both washers make full contact with the tank wall to obtain a water tight seal. Ensure that you comply with the tank manufacturers specifications


When adding additional fittings it is recommended that either a thread sealing paste or thread sealing tape be used on all threaded connections. We recommend Loctite 5331