Source/Deuter 3L hydration bladder Source/Deuter 3L hydration bladder

If you have a hydration bladder made by Source (or Deuter, which are re-badged Source hydration bladders), you may have run into an issue with the hose becoming harder and harder to insert into the bladder, or with a leak in the connection.

It is very likely that your problem is with the O-ring at the end of the hose, and that replacing the O-ring will fix the issue. This one:

Hose connector Hose connector

A #6 O-ring will fit perfectly. This is available at most hardware stores. The dimensions of a #6 O-ring are:

DimensionSize (in)Size (mm)
Outer Diameter (OD)7/16"11 mm
Inner Diameter (ID)5/16"8 mm
Cross Section (CS)1/16"1.5 mm

#6 O-rings #6 O-rings