needle system:DY*3 working area:800*270mm needle bar stroke:56mm alternating movement:4-8mm On the basis of GB-243, useing double shuttle, needle gauge can be adjusted according to your requirement, at the present, there are 1/4'', 3/8'',5/16''. 1/2''.Suitable for stitching all the extra heavy-weight materials, such as safety belts, tents, seatings, shoes, bags, golf bags......etc.