The reason for the 3 stars is that the AXE reservoir drying clip is not compatible with all Mazama reservoirs. I bought and really enjoy using the DUAL™ 2L Hydration Reservoir, however it does not have the full-length handle which you need for the AXE drying clip to work properly. It will keep my reservoir open, but it pops out easily. I would not recommend the clip if you are using it with any reservoirs that do not have the full-length handle! I do recommend you give Mazama products a try, very good quality, well priced and customer service that responds quickly to your questions or concerns. Shipping was great as well (UPS).