The original bite valve fell off my REI Hydration back pack. Fortunately you can buy these parts separately. This bite value and magnet are an exact fit for my pack. The magnet lined up perfectly. Suggest a small clamp on the hose if you use the hydration pack a lot. EMS sent it to me very quickly.
This is a great little bite valve with a strong magnet. I have used it twice so far and like the design. The base magnet has an attachment system for attaching to a 1" strap.
If you plan to use the reservoir in different settings, you might consider buying one for each setting so you don't have to move the base magnet. I.e., I have one on my daypack and one on my lifejacket.
I have used this system for some time now. after 2 years of biking season I finally bit through the little rubber mouth piece. Only [$] to replace. can't beat it!! The magnet system is SOOO much better than just having it bounce around while riding. Best system I have seen yet!!
I thought my hammerhead was lost when I couldn't find a replacement, having bitten a hole in the mouthpiece. [...]. thanks!