2-Ear Pinch Clamp, Stainless, 0.512 - 0.592 Inch Clamping Range, 0.295 Inch Width

Right in the sweet spot, actually. The clamping range on this one runs from 0.512 to 0.592 inches, so 0.55 puts you near the middle with room on both sides. That's generally where you get the most consistent compression. One thing worth knowing on installation, close the first ear all the way down before you touch the second one. Then bring the second ear in until the first opens back up just a hair, roughly a sixteenth of an inch. That spring-like tension is what keeps it locked down against pressure swings and vibration over time.