Anticoagulant protein which binds to the gamma-carboxyglutamic acid-domain regions of factors IX and factor X in the presence of calcium with a 1 to 1 stoichiometry. Also inhibits platelet aggregation by binding to platelet glycoprotein Ibalpha (GP1BA) and functioning as a blocker of vWF. Is devoid of hemorrhagic and lethal activities. Possesses antithrombotic and thrombolytic activities. Also hydrolyzes the Aalpha-chain of fibrinogen. Does not affect the Bbeta-chain and the gamma chain (By similarity). Heterodimer of subunits A and B; disulfide-linked. Expressed by the venom gland. Belongs to the snaclec family.