The present invention provides a multivalent antibody or a heavy/light chain component thereof comprising: a heavy chain comprising a constant region fragment, said constant region fragment located between two variable domains which are not a cognate pair, the heavy chain further comprising an Fc region with at least one domain selected from CH2, CH3 and combinations thereof, with the proviso that the heavy chain contains no more than one CH1 domain and only contains two variable domains, and a light chain comprising a constant region fragment located between two variable domains which are not a cognate pair, wherein said heavy and light chains are aligned to provide a first binding site formed by a first cognate pair of variable domains and a second binding site formed by a second cognate pair of variable domains.