A belt has a sealing ring disposed in an annular recess of the belt and two tightening lugs born by the ends of the belt. The edges of the recess form wedging steps for the edges of the sealing ring which substantially occupy the entire width of the recess. The ends of the belt exhibit a sealing arrangement which includes lateral tabs, that are formed at the second end and which extend widthwise on the belt, from one edge of the belt to the recess such that each lateral tab includes a part of one of the wedging steps.