Tasks involved in dressing, such as pulling a zipper or buttoning a shirt, involve resistive pinching movements which accentuate "zigzag" deformities common to arthritic fingers.  Manipulating garment fasteners is particularly difficult for people with joint swelling or those with moderate to severe arthritic finger deformities.  These devices help you carry out your dressing activities independently.  Their ergonomic design help in preventing aggravation of joint pain and deformities.