Antagonist of the alpha-2 subunit of the integrin alpha-2/beta-1 (ITGA2/ITGB1) on human platelets and endothelial cells. This protein inhibits collagen-stimulated activation of human platelets in a dose-dependent manner. In addition, it antagonizes the binding of monoclonal antibodies against the alpha-2 subunit of integrin alpha-2/beta-1 to platelets and it coimmunoprecipitates with this integrin. Heterodimer; disulfide-linked. Expressed by the venom gland. Does not block the glycoprotein VI (GP6) and does not inhibit platelet activation induced by ADP-, and thrombin. Belongs to the snaclec family.