Abstract: A reusable coupling adaptable to the ends of a tube, the coupling including a nipple (2) having a toothed end (7) designed to be inserted into the tube (1), its inside diameter corresponding approximately to the inside diameter of the tube, the nipple having an annular surface external to the tube. A peripheral ferrule (4) is mounted around the tube (1) and imprisons the tube in engagement with the toothed part (7) of the nipple (2). The ferrule (4) includes an inward annulus (5) which fits into a peripheral groove (6) on the surface of the nipple, while a seal (8) is provided within the groove to be contacted by the annulus (5). The ferrule (4) is radially compressible and is immobilized and fixed to the periphery of the tube (1) by a connection assembly made up of two connectable parts (9, 10) mounted around the end of the tube on either side of the ferrule, and which compresses the ferrule after it has been fitted on the tube.