That settup is identical to the one my lnspira frame came with, about 10 yr. old. I couldn't use it as it wasn't compatible with my Bailey midarm, but the lady l gave the parts to uses it on her Grace frame with her Husqvarna Mega quilter. You must have encoder wheels attatched to the carriage...one for the horizontal tracks, the other on the carriage tracks, and their wires plug into the blue box. The dial allows you to lengthen or shorten your stitch length according to your preference.