Just got this in the mail and attached it to my scope. I'm using it to clamp a 60mm doublet as a guide scope on top of my main scope. This thing is rock-solid. It clamps on firmly. The knobs are large enough to manipulate easily. The spring-loaded design means the clamp opens as wide as possible when I want to remove it from my dovetail bar, so it takes fewer turns to release. The guide pins mean the two independent clamps, each with only one knob, glide in and out straight and square. And the base is one solid piece with lots of mounting options. (I'm using the center hole and one slot.) Looks-wise, the anoziding is smooth with no blemishes. I like the two-tone look with the silver knobs. It's just a well-done, polished piece of equipment. My only issue, and it's a very minor one, is the knobs do have some friction and resistance as I turn them, so they don't just rotate freely. This is likely due to the spring-loaded clamps creating some pressure on the screws that open and close the clamps. But, again, this is nitpicking, and the knobs are a good size with good shape to grasp them. And, honestly, this friction means the dovetail won't open on its own from vibration, transportation, or bumps. That thing is staying closed! If all parts from Primalucelab are built this well, I'll happily consider buying more of their gear when I need parts. This is really good stuff!