The elastic straps on the front of the BMW Multi Vario tank bag stretch and deteriorate over time. I replaced mine at home without issue by first cutting the elastic from where it is stitched to the bag, then cutting the leather connecting the metal hook to the elastic. I used a 9" long by 1" wide strip of elastic for each side. (My wife had this in her sewing room and uses it as waistband elastic.) I looped it through the metal hook, pierced it with an awl, drilled a hole in the bag, and attached with a black anodized allen head screw, using a hole blank (available at Loew's) with nut and washer on the inside. It took me longer to thnk of it than to do it, most of the time is assembling the materials - elastic strap, screw, nut, washer, and hole blank. I also put plastic nipples on the end of the bolt from Loew's, to keep the screw end from damaging the tank bag contents.