Review on Zefal Wiiz 2016 Side Mount Bottle Cage by David Herrera

I bought two of these for my mountain bike. I liked the fact that they are reversible and very light. The problem is that the two are flexible and won't securely hold a water bottle on rough terrain. I've lost my water bottle a couple of times so now I'm looking down at the rough sections to see if I need to go back. I use insulated 21 oz CamelBak Podium bottles as the large/tall 25 oz Podium bottles are too heavy and very easy to fall out.