The Bernina #C21 10/36 Double Fold Binder attachment is used with the Binder Accessory Attachment on the L890. Due to the top bottom double-fold binder, fabric edges and necklines can be perfectly bordered with bias tape. The unfolded tape is inserted through the attached guide rail, folded over twice on the upper and lower sides of the bias tape and sewn on with a cover or chain stitch. For the perfect look, the bias tape can also be self-made. Tapes of 38 mm width result in a finished width of approx. 10 mm. Tapes of 60 mm width result in a finished width of approx. 15 mm. An attachment adapter is required to use the tape binder.