The walking foot is a moving feed system that holds and moves fabric between the presser foot upper feed dog and the machines's lower feed dogs to better control difficult fabrics as well as multiple layers of fabric
The walking foot is great for quilting, sewing when matching prints or plaids or fabric drift is an issue. Fits most low shank sewing machines
For sewing knitted fabric, effectively reduce the jump needle
For sewing special slippery fabric, leather and so on. Keep conveying smoothly
To keep the upper and lower layers of fabric transport synchronization, reduce the wrong layer (for multi-layer fabric, cotton cloth)