This is a foundation component: a compact 2.43″ × 1.31″ diamond-shaped aluminum plate with a 2-hole AMPS pattern (1.912″ spacing), topped with a B Size ball. It's a smaller, lighter alternative to RAM's round plate — the diamond hole pattern is used by a wide range of RAM and third-party cradles.

Features

• Diamond plate features industry-standard AMPS hole pattern and measures 2.43″ × 1.31″
• Compatible with several RAM device holders and cradles; ball-and-socket technology allows near-infinite adjustability
• Made of powder-coated, marine-grade aluminum for durability and reliability in the most demanding environments
• Backed by a lifetime warranty

How RAM's modular system works

Every RAM mount is built from up to three parts that click together, and the same parts mix and match across RAM's entire catalog:

• A base — clamps, bolts, or straps onto the vehicle (a rail, a roll bar, a dash, a windshield, or a device's own housing).
• An arm — connects two RAM balls together. It locks at any angle, so once mounted you can tilt, rotate, and reposition the device freely, then lock it firmly by hand.
• A cradle or holder — grips the specific device (tablet, phone, GPS unit, camera).

Not every product includes all three parts — some are just the base, some bundle a cradle, some are a complete kit. Further down this page we say plainly which parts this specific product includes, so you know exactly what you're getting and what, if anything, you'd need to add.

The ball size determines what it can carry. RAM uses five ball sizes, each rated for a different weight and duty class:

• A Size — rarely used; costs more to make than B Size but carries less. Reserved for small, low-profile items like security cameras where bulk matters more than capacity.
• B Size (1″ ball) — RAM's most common size, standard duty. This is what RAM recommends for phones, GPS units, and light tablets in normal use.
• C Size (1.5″ ball) — heavy duty. Used for larger tablets, handheld computers/scanners, CB radios, and anything mounted somewhere that gets a lot of vibration or shock — exactly the case in a tractor, ATV, or UTV cab.
• D and E Size — reserved for large monitors and specialist/military equipment; rarely needed outside those cases.

This product uses a B Size ball (1″ / 25 mm), RAM's standard-duty size, recommended for phones, GPS units, and light tablets in normal use. For a larger or heavier device — or one that will take real vibration in a tractor, ATV, or UTV cab — step up to the C Size diamond base (RAM-238U) instead.

Rule of thumb: if the mount will live somewhere that's frequently jostled, vibrated, or under constant load — an off-road vehicle like a tractor, ATV, or UTV — RAM recommends stepping up to the larger ball size for extra stability, even if a lighter mount would technically hold the device's weight.

Diamond plate or round plate? This diamond plate is a compact 2.43″ × 1.31″ footprint with a single 2-hole AMPS pattern (1.912″ center-to-center spacing) — smaller and lighter than RAM's 2.5″ round plate (RAM-B-202U), which uses a 4-hole pattern. Choose the diamond plate when you know your cradle is drilled for it, or when space and weight matter more than having the widest possible holder compatibility; choose the round plate when you want the broadest range of compatible cradles.

No tools required, on purpose. RAM arms are designed to be tightened by hand only — there's no official torque spec, because the ball-and-socket joint is meant to be adjustable in the field without a wrench. If hand-tightening doesn't hold your device firmly, that's usually a sign the ball size is undersized for the device — sizing up solves it, rather than over-tightening.

Aluminum or composite — both are built for the outdoors. RAM mounts are made from marine-grade aluminum or high-strength composite, interchangeably depending on the part; both carry a lifetime warranty and similar weight ratings. Aluminum's powder-coat finish handles rough vibration and shock slightly better; composite skips the paint entirely, so it has nothing to chip, and is often preferred in high-corrosion or salt-air environments. Neither choice is "worse" — it's a trade-off between finish and environment.

Specifications

Frequently asked questions

Does it come with mounting hardware?
No — RAM recommends #10 screws suited to the material you're mounting into. A local hardware store or your vehicle's manufacturer can confirm the exact screws or bolts for your specific panel.

What screw sizes fit the holes?
#8, #10, M4, and M5 are the most common. If you pair this with a RAM holder, the holder ships with the hardware it needs.

B Size or C Size diamond base — which do I need?
B Size is RAM's standard recommendation for phones, GPS units, and light tablets. If you're mounting something larger, or it'll sit somewhere with constant vibration like a tractor, ATV, or UTV cab, choose the C Size version (RAM-238U) instead.

Does it include an arm or holder?
No — this is the diamond base plate and ball only. Pair it with a B Size double-socket arm and a cradle drilled for the diamond pattern to complete the mount.

Is drilling required?
Yes — the diamond plate is bolted or screwed down, either to a flat surface or to a matching diamond-pattern device holder.

What's the difference vs the round plate?
See the section above — same ball size options, but this diamond plate is smaller and lighter with a single 2-hole pattern, while the round plate (RAM-B-202U) has a wider 4-hole pattern and broader cradle compatibility.