A harness (10) for use with breathing apparatus comprises: a back plate (11); two support straps (13, 14), each of which extends between an upper part of the back plate and a lower part of the back plate, the two support straps being disposed on opposite sides of a central axis of the back plate (11); and a tension equalizing mechanism (15, 16; 30, 32) connected to the support straps and being arranged such that, when tension is applied to a first strap (13, 14) of the support straps, it acts to transfer the tension to the other, second strap (13, 14), thereby increasing the tension in the second strap, the tension equalizing mechanism being resiliently biased towards a neutral configuration.