a strap fastener includes a fastener body on which a strap is retained , and a socket member adapted to be mounted on the fabric of a bag to retain the fastener body for connecting the strap to the bag . the fastener body has a plug with an enlarged head snappingly receivable in a stepped bore formed in the socket member . the fastener body is rotatable about the axis of the plug with respect to the socket member . with this construction , the strap is connected to the bag with utmost ease and can be adjusted in a desired posture to suit with the physical characteristics of the user .