RAM X-Grip iPhone 8 Plus 5.5 Holder Double Socket Arm & Brake-Clutch Reservoir U-Bolt Mount RAM-B-174-UN10U (sku 44552)RAM X Grip iPhone 8 Plus 5. 5 Holder with Double Socket Arm and Brake Clutch Reservoir U Bolt Mount. RAM B 174 UN10U The X Grip is a spring loaded holder which allows for a perfect fit to the phone. Rubber coated tips will hold the device firm and stable. Constructed from high strength composite and stainless steel. Holder Dimensions: Minimum width 47. 6mm Maximum width 82. 5mm Depth 22. 2mm. The Mount fits to both brake clutch reservoirs and rails