Heavy Chain Only Antibody (HCAb) binds antigens just via the variable domain of the heavy chain, hence enabling easy cloning of the DNA encoding this binding domain, which is named as a single-domain antibody or heavy-chain-only VH (VHH). The discovery of heavy chain antibodies has led to unprecedented opportunities in cancer therapy. Recombinant VHHs are small (about 15-20 kDa) and strictly monomeric, they are able to bind their target with nM affinity, as well as with being stable in an extensive pH and temperature ranges. https://www.creative-biolabs.com/bsab/tetravalent-heavy-chain-only-antibody-hcab-generation-service.htm