RAM Mounts has built one of the most trusted mounting systems in the world around a deceptively simple idea: a spring-loaded cradle that expands and contracts to grip almost any device, in or out of a case, without needing a model-specific adapter. That cradle is the X-Grip, and it comes in five sizes covering everything from a basic smartphone to a 12-inch iPad Pro.
The catch is knowing which size to buy. Order the wrong one and your device either rattles around loosely or won’t fit at all. This guide breaks down every X-Grip size, what devices each one fits, and how to pick the right one for your setup — including how to use the X-Grip with mounting hardware you may already own.
| Model | Width Range | Best For |
|---|---|---|
| RAM-HOL-UN7BU (X-Grip) | 0.875″ – 3.25″ | Standard smartphones |
| RAM-HOL-UN10BU (X-Grip Large) | 1.75″ – 4.5″ | Large phones & phablets |
| RAM-HOL-UN8BU (X-Grip II) | 2.25″ – 5.75″ | Small tablets, iPad Mini, GPS units |
| RAM-HOL-UN9U (X-Grip III) | 6.25″ – 8.1″ | Full-size tablets (iPad, Galaxy Tab) |
| RAM-HOL-UN11U (X-Grip V) | 7.25″ – 8.75″ | Extra-large tablets, iPad Pro 12″ |
How the X-Grip System Works
Every X-Grip cradle uses the same basic mechanism: four spring-loaded rubber-tipped arms that grip the sides and bottom of your device. Squeeze the arms open, drop your phone or tablet in, and the springs hold it in place. Getting it back out is just as fast. There’s no cradle to configure, no model-specific adapter to find, and no reason to remove your case first — the rubber tips grip plastic, silicone, and rubber cases equally well.
Each cradle ships with a 1-inch ball attached to the back (the X-Grip III uses a different ball size — more on that below). That ball connects to any standard RAM B-size mounting arm, which is the most common size in the entire RAM ecosystem. If you already own a RAM suction cup base, a RAM handlebar mount, or any other RAM arm with a 1-inch ball socket, the X-Grip cradle snaps directly onto it. You’re buying a cradle, not an entirely new mount.
RAM backs every X-Grip with a lifetime warranty. The construction is high-strength composite with stainless steel hardware — built to take real-world punishment, not just sit on a desk.
Which X-Grip Size Do You Need?
The most important measurement is your device’s width — measured with any case or skin you plan to keep on it. Don’t measure the naked phone and assume the case won’t matter. A thick protective case can add 0.25 inches or more to the width, which can push you from one size category to the next.
X-Grip (RAM-HOL-UN7BU) — Standard Smartphones
The original X-Grip handles devices from 0.875 inches to 3.25 inches wide, which covers most standard-size smartphones without bulky cases. If you’re running an iPhone 15 standard, a Samsung Galaxy S24, or anything in a slim case, this is likely your size. One caveat: devices at the minimum 0.875-inch width need to be at least 4 inches tall to seat properly in the cradle — the arms need something to grip vertically. Check RAM-HOL-UN7BU on Amazon.
X-Grip Large (RAM-HOL-UN10BU) — Large Phones & Phablets
The Large X-Grip covers 1.75 inches to 4.5 inches wide — the right size for iPhone 15 Plus, iPhone 15 Pro Max, Samsung Galaxy S24 Ultra, and virtually any large Android in a standard case. This is the size we recommend for most people buying today, since modern flagship phones have grown significantly since the original X-Grip was designed. When in doubt between the standard and the large, go large — you can always use the tether for added security. Check RAM-HOL-UN10BU on Amazon.
X-Grip II (RAM-HOL-UN8BU) — Small Tablets & iPad Mini
The X-Grip II spans 2.25 inches to 5.75 inches wide, which puts it squarely in small tablet territory. This is the right size for the Apple iPad Mini, Samsung Galaxy Tab 7, and most 7-inch GPS units with their mounting cradle attached. Devices at the 2.25-inch minimum need to be at least 7 inches tall to fit correctly. Check RAM-HOL-UN8BU on Amazon.
X-Grip III (RAM-HOL-UN9U) — Full-Size Tablets
The X-Grip III handles 6.25 inches to 8.1 inches wide — full-size iPad, iPad Air, Samsung Galaxy Tab 10.1, and similar 10-inch class tablets. This is the one size in the lineup that uses a different ball: the RAM-B-202U large ball rather than the standard 1-inch B-size ball. That means it is not directly compatible with standard B-size arms. If you’re building a new mount setup around this cradle, make sure your arm matches. Check RAM-HOL-UN9U on Amazon.
X-Grip V (RAM-HOL-UN11U) — iPad Pro & Extra-Large Tablets
At 7.25 inches to 8.75 inches wide, the X-Grip V is built for the iPad Pro 12.9-inch and other oversized tablets. There’s very little overlap between this and the X-Grip III — if you have a 12-inch display tablet, this is your size. Check RAM-HOL-UN11U on Amazon.
Mounting Base Options
The X-Grip cradle is only half the system. You also need a mounting base that attaches to your vehicle, handlebar, or surface. RAM offers several options that all use the same ball-and-socket connection:
U-Bolt Base — clamps around a handlebar or roll bar. The go-to for motorcycles. Fits bars from 0.5 inches up to 1.25 inches in diameter, covering most Harley-Davidson handlebar configurations. See our Harley-Davidson phone mount guide for specific motorcycle setup recommendations.
Tough-Claw Base — tool-free clamp for round, square, or irregular rails from 0.625 inches to 1.14 inches. Popular for kayaks, ATVs, bicycle handlebars, and seat posts. No tools required to install or remove.
Suction Cup Base — attaches to flat glass surfaces like car windshields. Not suitable for motorcycles or any high-vibration application, but reliable for car and truck windshield use.
Composite Mirror Base — bolts onto the mirror stem of most vehicles. A cleaner install than suction for car use and leaves the windshield unobstructed.
Wireless Charging & MagSafe Options
RAM now offers wireless charging versions of their phone mounts under the Tough-Charge and Quick-Grip Wireless lines. These feature Qi wireless charging built directly into the cradle face and are MagSafe compatible — meaning MagSafe charging still works through them on iPhone 12 and newer. They connect to the same B-size ball system as the standard X-Grip, so they swap directly onto any existing RAM arm.
For motorcycle use specifically, the RAM wireless charging handlebar mounts are the recommended choice for Touring riders who run navigation continuously on long rides and don’t want to manage a charging cable. The U-bolt base versions are designed with the vibration dampening needed for motorcycle applications.
Why the Modular System Matters
The real value of the RAM X-Grip isn’t any single cradle — it’s that every cradle, arm, and base in the system uses the same ball-and-socket connection. Buy an X-Grip cradle for your motorcycle handlebar mount, and that same cradle transfers to a suction base in your car, a Tough-Claw on your kayak, or a desk mount in your office. When you upgrade your phone, you replace only the cradle. When you add a new vehicle, you add only a base. Nothing is wasted.
That modular philosophy is why RAM has remained the standard recommendation for serious riders, off-road drivers, and field workers for decades. The upfront cost is higher than a $12 Amazon special, but the system pays for itself the moment you use the same hardware across multiple applications.
