A blind for a building opening, and having; an upper blind roller, located in an upper region of the head rail, a lower blind attachment located in a lower region of the head rail, an upper blind stored on the upper blind roller, a lower blind stored on the lower blind attachment, upper and lower blind control mechanism to operate the blinds and the upper blind roller being located with an upper axis along an upper plane in the head rail and the lower blind attachment is located on a lower axis along a lower plane within the head rail, the axes being displaced vertically from one another, and in which the upper blind depends down beside a predetermined side of the lower blind attachment, and in which the lower blind depends down alongside said upper blind, so as to provide a head rail having a slim, aesthetically pleasing profile.