Summary Mr. Pinchy. With a couple bolts, washers and nuts make a powerful adjustable hose clamp. Use it for broken air lines in rigs so you can get home, isolate vacuum hoses for testing engines or adjust the flow from air compressors and fish tank bubblers. Don't bother downloading the assembled STL it's just there for the Thingview. No wrench needed, just turn the knobs. Post-Printing 5/16 th inch imperial hardware. 1/2 inch wrench fits the nuts. Yeah I know metric is better, I'd use it if I could get it for a decent price but I can't here. How I Designed This Sitting next to a grumpy baby.