A sleeve for use in an assembly for coupling a wristworn device to a first end of a strap. The sleeve has a first end dimensioned to be received in the recess in the inner face of the first lug of a wristworn device, an inner cavity dimensioned to receive therein the first end of a conventional spring bar, and a retractor coupled to the sleeve for urging the first end of the spring bar towards the second end of the spring bar. The second end of the spring bar is coupled to the second lug, the spring bar is coupled to the strap, the first end of the spring bar is positioned in the inner cavity of the sleeve and the first end of the sleeve is coupled to the first lug. A removable retractor for use with a spring bar, which allows for the use of a plurality of spring bars and therefore, lends itself to widespread use and retrofitting of an assembly that couples a strap to a wristworn device, is also provided.