High performance, high pressure, high criticality applications. These are Australian-made Tridon products as well. 304 grade stainless steel. The nature of construction of the T-Drive mechanism is that it is incredibly strong and can impart huge pressure on the hose. With this in mind the edges of the clamping band is rolled upward slightly. This stops the edge of the band cutting into the hose. You will also notice with T-bolt drive clamps that their actual clamping range is so much narrower. You must be more careful in selecting a clamp that is appropriate for your application. Width: 19mm Clamp Range: 52-55mm