Quality control is easy with the close-it® control seal. In contrast to normal labels, close-it® adheres well to sacks that are coated with powder (plaster, flour etc.). close-it® is a self-adhesive seal (aluminium backing), which adheres very firmly. Sacks, cartons etc. which have been pierced and sampled by powder-proof (or other samplers) can be hermetically re-sealed with close-it® control seal. The seal can be labelled with pen, pencil or felt-tip pen.