This is a new style binder used to insert bias binding or tape along the edge of the garment. 

This binder folds the tape in half around the fabric then underfolds both top & bottom edges of the binding, making a CLEAN finish top & bottom. Finish size is about 1/4 of the tape size, may a little different vary with type of material.

The binder does not need to be removed after use, just swing it out of the way. The position of outlet can be adjusted to be backword or forward and left or right by the three screws on the binder.you need to adjust it to be aligment with needle to make perfct finish work.

Screws for attaching the binder are included. it fits most Singer machine, but not sure fit some PFAFF DURKOPP ADLER sewing machine.