Lectin that primarily recognizes glycans with a non-reducing terminal N-acetylgalactosamine (GalNAc), with a preference for the alpha- over the beta-anomer. Can also bind non-reducing terminal galactose (Gal) residues but with a lower affinity. Strongly interacts with glycolipid type glycans with terminal non-reducing Gal or GalNAc but fails to bind sialylated or fucosylated forms of the same glycans. Strongly interacts with galactosylated N-glycans, displaying highest affinity for alpha-1-3 branched mono-antennary N-glycans but also binding to multi-antennary glycans. Homodimer.