4mm-25mm Pipe Clamps for choose Fuel Spring Clip Vacuum Silicon 65Mn Autos Autos Spring Clip Fuel Oil Water Hose Clamp. Ordered 4mm clips, measured internal diameter of hose clips with engineering verniers and perfect at 0.158 thousands inch or 4.01mm, delivery was very quick from Cory Miller's Store. very reasonable price for item, only negative aspect for the clips is that they have been hardened to much, and are very brittle; when expanding / opening the clip to fit over the tube, pipe, or hose; the clip breaks with very little pressure applied. This means the metal has been hardened to much, for any looking to purchase these ultra small 4mm clips, you can overcome this problem by heating the clips to roughly 300 degree C, then allow them to cool normally, dont quench or dunk in water or oil, this will temper or anneal the metal making it softer and less brittle.
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