Diabody is a dimer of scFv which consists of VH and VL domains connected by a short peptide linker. The linker is too short to form intrachain pairing of VH and VL domains. Instead, two such scFv fragments are co-expressed to form multimers, named bispecific Diabody, by inter-chain pairing (cross-over pairing) of VH and VL domains. Bispecific Diabody has monovalent specificity for each antigen (1+1 antigen-binding valency). Similarly to tandem scFv, it has a short half-life and better tissue penetration.