The inside dimension of this hoop is 4 1/16″ (4.062″, or 103mm)
Actual sewing area depends on brand of machine approximately 3 1/4″ (3.27″ or 83mm)
Mighty Hoop has a diverse selection of sizes and matches perfectly with Smartstitch embroidery machines.
Youtube video on adding custom frames to the S-1201:
Youtube video on adding custom frames to the S-1501:
Youtube video on separate and keep your Mighty Hoop:
