Abstract: An unfoldable card (1) comprising first and second portions (2, 3) which are moveable in relation to each other and which are joined to each other by an elastic means (4), said card selectively adopting a closed configuration wherein the elastic means (4) is stressed and the first and second moveable portions (2,3) are moved towards each other, and an open configuration wherein the elastic means is de-stressed and the first and second moveable parts (2,3) are moved away from each other. The card is provided with a blocking means (5) enabling the card to be locked in the closed configuration thereof, said blocking means (5) comprising means causing the card to pass automatically in a delayed manner from the closed configuration to the open configuration.