... by hand 2. Easy to operate 3.single grommet , save cost and manpower 2012 New steel single ring manual ... 2 parts/set, positive ring and negative ring. To make grommet need install positive ring, and negative ... and when put flex banner in machine, easy to move the negative ring out, press machine handle ... 1000pcs/hour; light weight, rivalrous price. 2012 New steel single ring manual grommet machine