RAM Mount® Weight Capacity: Which Ball Mount Do I Need?
RAM Mount Ball Size and Weight Capacity Guide
Choosing the right RAM ball size matters. RAM Mounts use different ball-and-socket sizes to suit different devices, weights and mounting environments.
For most popular setups, you will usually be choosing between B-Size, C-Size and D-Size RAM components. Smaller devices usually suit smaller ball sizes, while heavier devices and rougher applications may need a larger size.
Which RAM ball size do I need?
The table below gives a practical comparison of the most common RAM ball sizes, diameters and recommended weight capacities.
| Ball size | Ball diameter | Recommended weight capacity | Common uses | Shop components |
|---|---|---|---|---|
| B-Size | 1 inch | Up to 2 lb / 0.9 kg May suit up to 5 lb in light-duty applications. | Phones, small GPS units, lightweight cameras and compact accessories. | B-Size Components |
| C-Size | 1.5 inches | Up to 4 lb / 1.85 kg May suit up to 10 lb in light-duty applications. | Tablets, larger devices, medium-duty vehicle mounts and many work setups. | C-Size Components |
| D-Size | 2.25 inches | Up to 6 lb / 2.75 kg May suit up to 15 lb in light-duty applications. | Heavier tablets, marine electronics, larger screens and more demanding vehicle applications. | D-Size Components |
Important note: these weight capacities are a guide only. Vehicle vibration, mounting angle, arm length, road conditions and the type of device being mounted can all affect the best RAM ball size for your setup.
When in doubt, it is often worth stepping up one ball size, especially for heavier devices, longer arms, rougher roads, marine use, 4x4 driving or commercial vehicles.
Quick starting points
If you need an A-Size or E-Size RAM ball-and-socket setup, contact us and we can help point you in the right direction.
Watch: RAM ball sizes and applications
The videos below help explain RAM ball sizes, weight ratings and the types of applications each size is usually suited for.
Still unsure which RAM ball size you need? Send us your device model, approximate weight, mounting location and how you plan to use it. We can help you choose the right holder, arm, base and ball size.
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