The SM4RM023 Robust universal car cup holder phone mount is part of Arkon's Robust Mount Series. This sturdy mount's one-piece base fits easily into any car or truck cup holders, and twists to expand to up 3.5 inches in diameter. The mount features Arkon's Mega Grip phone holder, which holds smartphones with cases (including Otterbox) up to 3.25'' wide with no height restrictions, including iPhone 11 Pro Max, iPhone 11 Pro, iPhone 11, iPhone XS Max, iPhone XS, iPhone XR, iPhone 8 and 8 Plus, Samsung Galaxy Note 9 and Note 8, Galaxy S10, S9, and S8, LG G6, G5, and G4, and Nexus 6 and Nexus 5. The phone holder's unique spring-loaded side-arm mechanism provides a strong grip that's easy to use, yet makes it easy to insert or remove the smartphone. Just set your phone in the holder and close the arms to lock in place. A push of the holder's side button releases the phone. The Mega Grip Holder is universal, making it compatible even when used with a large protective case or skin.