Apparatus for providing negative pressure at a wound site, the apparatus comprising: a suction pump (20) to generate a negative pressure a reservoir of negative pressure (22) a valve member (24) arranged for selectively providing a path of fluid communication between the reservoir (22) and the wound site (10) while a negative pressure in the tank negative pressure (22) is greater than a negative pressure threshold, thereby providing a negative pressure at the desired site of the wound and wherein in response to a pressure in the tank negative pressure (22) decreases to the negative pressure threshold, the suction pump (20) operable to reset an initial negative pressure in the tank negative pressure (22 ), wherein there is a coupling element further valve (26) between the reservoir of negative pressure (22) and the suction pump (20), the element further valve (26) being configured to connect the vacuum pump to the tank negative pressure (22) when the pressure in the element further valve (22) drops to the negative pressure threshold, the element further valve comprising: a channel member (48) having elements opposite sidewall (410) which can be located in a separate open configuration in which a channel between the side wall members and a closed configuration in which the side wall elements are supported is provided p ara close the channel wherein the side wall elements (410) are resilient and can be moved to said open configuration in which the channel (48) provides a path of fluid communication or to said closed configuration in response to a pressure difference in or the side wall elements.Aparato para proporcionar presión negativa en un sitio de herida, comprendiendo el aparato: una bomba de aspiración (20) para generar una presión negativa un depósito de presión negativa (22) un elemento de válvula (24) dispuesto para proporcionar de manera selectiva una trayectoria de comunicación de fluido entre el depósito (22) y el sitio de la herida (10 ) mientras una presi
