Three months or so. That is what I've read. But then again, if they say three months, and they (Arm and Hammer) are selling the stuff, it may actually last for six!
After it has completed its tour of duty in your fridge, you can use it with a vinegar chaser for your kitchen drain.
After it has completed its tour of duty in your fridge, you can use it with a vinegar chaser for your kitchen drain.