RAM® Mount Buying Guide: Choosing the Right Ball Size, Base and Holder

The first question is simple: what are you mounting? A phone, tablet, GPS unit, fish finder, scanner, action camera or rugged device will each need a different approach.

Check the device size, weight and whether it has a case. Protective cases can make phones and tablets much thicker than the bare device dimensions. If the device needs to charge while mounted, make sure the holder does not block the charging port.

For fleets or worksites, also consider whether the same device model will be used every day or whether different users will mount different devices. This will help decide between a universal holder and a form-fit cradle.

The holder is the part that physically grips or supports the device. RAM® offers universal holders, device-specific holders and holders for tablets, phones, GPS units, cameras and other equipment.

Universal holders are useful when multiple device sizes need to fit the same mount. They are a good choice for shared vehicles, family vehicles, delivery drivers, tradies and businesses where phones may be upgraded often.

Form-fit or device-specific cradles are better when the same device will be used long-term. They can offer a cleaner fit and are often preferred for fleet, enterprise and dedicated work setups.

Tablet holders need extra care because tablets are heavier and often used with rugged cases. Check the tablet dimensions with the case attached, not just the tablet model.

RAM® ball size affects strength, compatibility and how much weight the system can support. The most common sizes customers compare are B Size, C Size and D Size.

B Size is commonly used for phones, small GPS units, action cameras and lighter setups. It is compact and practical for everyday vehicle use.

C Size is stronger and is often used for tablets, rugged devices, larger GPS units, commercial vehicles, forklifts, agricultural machinery and work setups.

D Size is larger again and is used for heavy-duty applications such as larger marine electronics, heavier screens and more demanding mounting environments.

The ball size must match across the arm, base and holder connection. B Size components should be used with B Size arms. C Size components should be used with C Size arms. Mixing sizes is generally not the right approach unless a specific adapter is being used.

The arm connects the holder to the base and allows adjustment. Arm length affects reach and stability.

A short arm is usually the most stable option. It keeps the device close to the mounting point and reduces movement. A standard arm gives more flexibility. A long arm gives more reach, but it can also increase vibration and leverage.

For rough roads, farm machinery, heavy equipment, motorcycles and boats, choose the shortest arm that still gives a usable viewing position. For desks, counters or low-vibration environments, a longer arm may be acceptable if extra reach is needed.

The base attaches the mount to the surface. This is one of the most important parts of the setup.

Suction cup bases are useful for temporary vehicle setups on smooth surfaces. They are convenient when the mount needs to move between vehicles, but they may not be best for heavy devices or high-vibration environments.

Tough-Claw™ bases are useful when there is a suitable rail, tube, bar or frame. They are popular for temporary or semi-permanent setups in vehicles, machinery, boats and work areas.

Drill-down or AMPS-style bases are useful for permanent installs. They provide a more stable foundation and are often preferred for fleet, work vehicle, warehouse, marine and industrial applications.

Track bases, rail bases and specialty bases may be suitable for kayaks, boats, motorcycles, desks and equipment-specific installations.