specialty： 1.Sritable for sewing snd feeding all kinds of hesvyweight materal.. 2.Excellent for sewing sharp curves. 3.Outstanding operation and maintain capacity, 4.Emlarg ing the feeding strength,reducing the frequency of stitch skipping and stitch gathering. 5.The rate of alternating virtical movecent will not changeevev if the thickcessof materials changed 6.Max left of the presser foot :16mm 7.MAX alternating vertical movement 6.5mm