Arkon's RV188 RoadVise premium universal car seat rail or floor car phone mount fits all smartphones with cases weighing up to 2 pounds and measuring up to 4 inches wide, including iPhone X, iPhone 8 and 8 Plus, iPhone 7 and 7 Plus, iPhone 6S and 6S Plus, iPhone 6 and 6 Plus, Samsung Galaxy Note 8, Note 5, and Note 4, Galaxy S8, S7, and S6, LG G6, G5, and G4, Nexus 6 and Nexus 5, HTC One M9, One M8, and One Max, Nokia Lumia 1520 and 1020, Motorola Moto G and Moto X. The holder's solid construction provides strength and reliability on the road by featuring a spring-loaded mechanism that expands to hold smartphones up to 4 inches wide. Arkon recommends using the RoadVise Holder with smartphones with skins and ruggedized cases. The RoadVise is designed to use two hands to install and remove your device. This is to make sure your device cannot be accidentally removed while adjusting viewing angle. The low-profile holder keeps rear smartphone cameras free for spontaneous pictures or videos. Just snap the holder onto the 17mm ball of the pedestal and secure with the included tightening ring. The car seat rail or floor mount is made of strong steel, and is ideal for those who need easy access to their smartphones but prefer mounting them somewhere other than the windshield or dash. Loosen the passenger seat track bolt with a socket wrench, insert the included seat track bolt bracket, and then retighten the bolt. Bend the 15'' gooseneck and rotate the swivel ball adapter head for 360° rotation for exact positioning of the cell phone. Optional floor brackets are included for installing the car dock directly into the floor of the vehicle. (Warning: Drilling into the vehicle's floor may damage the vehicle. Use caution and consult a mobile install professional to avoid drilling into any sensitive vehicle components.) The RV188 also functions as a Garmin GPS mount by removing the holder and revealing the 17mm ball mount base. It's a solid car mount solution that's perfect for your needs.