Automatic pull strips are glued so the card becomes 3-D when opened.
The long strip on the left is folded and glued. The far right side of the curved paper is not glued down and is pulled into 3-D position when the card is opened.
Often a slit is cut into the card and the strip runs through the cut and is folded and glued to the other side of the card for strength and to hide the pull strip. If this is done a second paper is needed in order to decorate the other side of the card.
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