The aircraft was quite small for its bomb load and range; it was allowed in part by a lift-generating, airfoil-shaped fuselage, which was another then-unusual feature (previously used e.g. on PZL.26 sports plane).
The bombs were carried in two-section bomb bay in the fuselage (with space for 4 bombs) and 8 bomb bays in the central section of the wings (with space for 16 bombs).