... , GB4-1 model is used to sew canvas, container bags, belts, leather, tent, luggage, etc Model GB4-1 is High speed ... , GB4-1 model is used to sew canvas, container bags, belts, leather, tent, luggage & thick material.Up-and-down feed dog ... head: 78kgNeed bar stroke: 58mmShuttle hook: SEIKO HSH-7-3 PP woven bag sewing machine GB4-1