Sewn closures are applied to open mouth bags by passing the bag top through a sewing machine. Prior to sewing, bag tops may be formed by hand or by automatic equipment. Where protection against sifting is desired, paper tape is added to the sewn closure, either over or under the thread as desired or a filler cord can be added.

The following equipment is available from Union Special:

 Styles BC100
- Portable bag closing machines styles 2200 and 3000
- Accessories for the portables such as pedestal, top lock spring balancer, movable tables etc.
- Automatic bag closing equipment with integrated machines series 2200, styles 1200LOE and 1500LOE
- Heavy duty bag closing machines styles 80800 and BC100
- Columns Styles 20600
- Feed-In Devices Styles 29900
- Square and round telescopic columns 20600
- Belt-type and slat-type conveyors 91605G and L
- Thread break detectors, thread cones and label dispensers
- Further accessories for bag closing units, such as movable or stationary bases and other devices

For details please see the technical descriptions, leaflets and sewing samples.