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