RAM® 方柱夾具底座，適用於寬達 3 吋的柱子 - C 尺寸

The rubber ball locks into my existing c-size arm with a solid click, and the clamp grabs my 3-inch rail without any wobble once I tighten it down. Feels sturdy enough to trust with my tablet on rough trails.

Took a bit of fiddling to get the screw tight enough on my 3" rail, but once it's set, that 1.5" ball holds my device rock-solid through gravel roads and highway bumps. The clamp base feels dense and sturdy, and it's cut exactly to the C-size components I already had.

The 1.5” rubber ball snaps into my C-size arm with zero play, and the clamp grips my 2.5” rail like it’s welded. Took under a minute to tighten down with the included knob.