Bag Styles, Tops and Closure Types

Valve top bags

A pre-formed valve in the top lets a filling nozzle push product in without dust escaping and without any closing step afterwards — the valve seals itself under the weight of the product. This is the standard choice for high speed automatic filling of powders, granules and cement.

Use it when: you fill more than a few bags a minute, or your product is dusty and you cannot afford airborne loss.

Sewn open mouth (SOM)

A flat open top that is filled through a standard spout or by hand and then closed on a sewing line or with a bag closer. Simple, inexpensive and flexible, with good tolerance for different fill weights.

Use it when: you fill manually or semi-automatically, or you want the cheapest bag that does the job.

Hemmed top

The top edge is folded over and stitched instead of being heat or cold cut. The result is a thicker, more comfortable edge for hand carrying and a neater appearance, at a very small cost difference.

Heat cut and cold cut

Heat cut seals the fabric edge as it cuts, which stops the weave fraying and gives a clean appearance. Cold cut is a plain cut and is the lowest cost finish. Both are open top constructions.

Block bottom / square bottom

A folded and pasted or stitched base that lets the bag stand upright like a paper sack. It carries a flatter, more rectangular face for printing and stacks neatly on a pallet or a shelf.

Use it when: the bag is displayed at retail, or you need the best possible print area on the front panel.

Pillow / tubular and gusseted

Pillow bags are a plain tube, cheap and strong. Side gussets fold the sides inward so a filled bag becomes a rectangular block, which loads out a container and a pallet far more efficiently.

How to choose, in one table

FAQ