Nattokinase is an enzyme that is extracted from Japanese natto (fermented soybeans, known in Japan as a superfood) Nattokinase typically varies from 2,000 FU per 100mg to 1,000 FU per 100mg. FU stands for fibrin units which is an activity unit quantifying Nattokinase supplement strengths. Research suggests Nattokinase may help lower plasma levels of certain proteins that effect blood flow. This can help support healthy circulation and overall cardiovascular health. Double Wood Supplements' Nattokinase supplement is manufactured and tested in the USA, Vegan Safe, Non-GMO, Gluten Free, and contains no fillers. Each bottle contains 120 capsules with 100mg (2,000FU) of Nattokinase each (60 two capsule servings of 400mg (4,000FU Nattokinase))