Both the 26601 10-Hour Fuel Moisture Stick (used with the CS506-L) and the CS205 10-Hour Fuel Temperature Stick (used with the 107-L) can be easily replaced in the field with a Phillips screwdriver and an adjustable wrench.
The dowels should be replaced each spring; more frequent replacements may be required in some environments. The more wet/dry cycles the dowels experience, the more frequently they will need to be replaced.