Applied with the automatic lubrication mechanism design, durable, and ensured the precise back-tacking seams. Adopting unison feed makes accurate and uniform stitch even on material with a rough, slipper, or tacky surfaces.

Applied with the new type of stitch length adjusting mechanism, precise stitch length setting and stitch length of forward-stitching and backing tacking could be easily adjusted. The special feeding mechanism design can be convenient for extra thick material feed. Suitable for stitching tubular and curved extra heavy-materials articles, such as shoes, bags, purse, etc.