the minimum of the band length augmented by the reversing link 21f and its two adjoining links 21 to a maximum dictated only by the exigencies of the circumstances in each instance therefore the effective length of the annular element 10 20 can be chosen in small incremental steps to fit the particular user i e to be neither too tight nor to loose when worn while the expansion capability conferred on the annular element 10 by the expandable properties of the band 10 itself lets the wearer take the annular element 10 20 off or put it on easily by slipping it past relatively larger circumference regions such as the hand it also should be mentioned that the transversely directed link connecting action besides enhancing the security of the connections brings about the possibility of decreasing the longitudinal dimension of the extension links 21 to a bare minimum this in turn results in reduction in the size of the increments by which the effective length of the annular element 10 20 can be adjusted and in concomitant improvement in the 34 fittability 34 of the element 10 20 to the particular user it is no longer necessary to bend sheet metal remove and replace staples and to deform.