Ideal Tridon 6712M51#12 Stainless Steel Worm Drive Clamp with 316 Stainless Steel Screw 67M Series, 11/16" to 1-1/4" Diameter, 9/16" W (Pack of 10)

Excellent quality.- 100% stainless steel clamp - band and strap.- Strong band material does not strip with high clamping force.- True to size.

I tried to use these to replace single use ear type clamps inside my hot tub. I was replacing the UV/Ozone unit and it seems likely I will have to do it again in the future, so I added some shut-offs on either side to avoid having to drain the tub. I ended up needing 6 clamps to seal pvc vacuum-type hose (with a pvc coil in the wall of the tube) to barb fittings. This is not a pressure line, it is free flowing circulation, but even before I finished filling the tub every joint leaked. At least I think every joint leaked, there was so much leaking I couldn't be absolutely sure they all leaked but it seemed like it. I have installed a large number of hose clamps in my life. I realize that you have to not over tighten nor under tighten. I started off with just what I thought would be the minimum, they leaked, so I tightened, and so on. I was using a screwdriver type nut driver and I'm not a gorilla, so I don't think it should have been possible for me to break or strip one of these considering the premium price. But on one of them the worm drive came loose from the band, another the threads stripped, see the photos. None of them sealed, or at least I gave up and replaced them all with the ear type clamps and had no trouble sealing the joints on the first try. They all seam to have bent out of round near the end of the worm drive where the band is actually just two skinny strips of steel. Which I suspect is why they didn't seal. Before using them they seemed like good quality. I gave them two stars since maybe if you were only sealing a softer type of tube they would work, the tubing I was using is very stiff, but the ear type clamps worked without a problem, so obviously not impossible to seal.