Protease-inhibitor that contains multiple distinct protease inhibitor domains. Probably has serine protease- and metalloprotease-inhibitor activity (By similarity). Expressed in pancreas, kidney, liver, placenta, and lung. The second BPTI/Kunitz inhibitor domain is able to inhibit trypsin. It has however no activity toward chymotrypsin, elastase, plasmin, pancreatic kallikrein, lung tryptase, plasma kallikrein, thrombin, urokinase or tissue plasminogen activator. Belongs to the WFIKKN family.