Potent inhibitor of collagen-induced platelet aggregation. It acts by binding to the integrin alpha2A domain and blocks collagen binding to integrin alpha-2/beta-1 (ITGA2/ITGB1). The gamma/delta subunits mainly contribute to this activity. Heterotetramer of subunit alpha, beta, gamma and delta; only the gamma and the delta subunits are disulfide-linked. Alpha-beta heterodimer and gamma-delta heterodimer associate orthogonally, giving a cruciform conformation (PubMed:19369383). This heterotetramer may covalently dimerizes thanks to the gamma subunit (PubMed:11121411). Expressed by the venom gland. Belongs to the snaclec family.