Stitch in the Ditch foot has a guide in the centre needle postition at the front of the foot that sits in the seam line. It will help to give an accurate line when stitching in the seam line (ditch) for patchwork or dressmaking.
 
Category  B C D E F G J K L 
 
How to use:-
Attach the Stitch in the ditch foot.
Engage the IDT system if available on your machine.
Select a straight stitch (or any stitch that has a centre needle position).
Place the quilt under the presser foot with the guide in the seam (ditch) of the pieced quilt.
The guide of the presser foot will follow the centre of the pieced seams.