The Medium-Small FRM-Designed Felt-Finished Accordion Bass Strap (formerly called "junior" size) is one of the best of its kind. For student-sized, and petite 120 bass accordions, having a 17-1/2 Inch Keyboard or smaller, the medium-small bass strap is probably the one needed for your strap replacement. The part of the strap showing outside on the back would be about 14-1/2". Check the measurement of the old strap against our size listed, to be certain whether you need the Medium-Small, or the Medium 19" Bass Strap. PLEASE NOTE: The picture is of the FRM-469 vinyl-finished strap, exactly the same size and shape as the FRM-470F (we knew that). NOTE: All the FRM Series Bass Straps are provided without end hardware but with rivets for changing it. A New Hardware Kit can be added to the order (see below). The hardware kit is available separately or installed. Ikeslist.com can perform the service of exchanging the strap for a flat rate of $100 which includes the new strap and any necessary new hardware. Just email Ike@IkesList.com for instruction on shipping us just the bass part. Please attach a photo to the email as some accordions are "odd".