4400 4420 OPERATION INSTRUCTION/PARTS MANUAL

Both the models adopt straight twin-needle and two horizontal hooks with auto lubrication for thread looping, sliding lever for thread take up to form two lines of lockstitch seam The upper shaft and lower shaft is connected by ball bearing and driven by teeth-type synchronic belt; plunge oil pump lubrication system. They adopt the compound feed mechanics of feed dog, needle bar and presser foot, even if for long stitch length and long material Theycan deal with them freely.