The instructions that come with most carboy handles don’t say this but NEVER carry a carboy by just the handle. Always support a carboy at the neck and by the bottom. Inspect your handle before use, keep the screw tight, and watch for wear on the rubber coating. If the coating is worn the diameter of the handle changes and the handle can get loose enough for the carboy neck to slip out.
There is Internet chatter that this device also fits many plastic Better Bottle type carboys. The minimum inside diameter of the neck ring is 1 7/8″ (48mm) and the maximum is 2 1/8″ (52mm)These MADE IN CANADA handles cost a couple dollars more than the Chinese ones. We think it is worth it for us to “carry” these instead of the cheaper ones.