the edge of the preformed opening being provided with incisions or notches for facilitating removal

Full Title

Containers specially constructed to be opened by cutting, piercing or tearing of wall portions, e.g. preserving cans or tins > Non-integral frangible members applied to, or inserted in, a preformed opening > Details of preformed openings > the edge of the preformed opening being provided with incisions or notches for facilitating removal