Between aerobar hydration systems have always been a novel, if not messy idea. Open top bottles, even with sponges or mesh, are prone to splashing if you hit a speed bump or rough section of road. Speedfil Hydration took a new look at bar mounted hydration with the Z4, a secure bottle mount that also holds your GPS unit. Unlike upright bottles that secure with oversized rubber bands, the Z4 attaches securely to the extensions with nylon cable ties. This top of the bar positioning means that bar width is no longer dictated by the width of your bottle. Additionally, the Z4 integrates a removable arm that houses the Garmin quarter turn bike computer mount sold separately so that your metrics will always be in plain view.