Doctor's Best Sustained Plus Immediate Release L-Arginine, Non-GMO, Vegan, Gluten Free, Soy Free, 500 mg, 120 Bilayer Tablets Size:500 mg Sustained plus immediate release l-arginine contains this conditionally essential amino acid in a bilayer tablet, with two tablets providing 500 mg of sustained release and 500 mg of immediate release l-arginine in a formula that allows for enhanced blood levels of this nutrient. most supplemental l-arginine is quickly absorbed into circulation and is extremely efficiently metabolized, yielding only a short-lived boost to l-arginine levels. sustained plus immediate release l-arginine tablets are specifically manufactured to immediately increase blood levels of l-arginine and then to sustain this beneficial increase continuously over an 8-hour period.l-arginine has been shown to support the cardio- vascular system, promote vigorous heart function and enhance healthy circulation throughout the body through its conversion to nitric oxide. research suggests l-arginine supplementation may also have positive benefits on athletic performance. Features: Has positive benefits on athletic performance Promotes a healthy cardiovascular system & enhances healthy circulation Gluten Free, Non-GMO, Vegan Label images may vary Product Details: Product Dimensions: 2.4 x 2.4 x 4.4 inches ; 4.8 ounces Shipping Weight: 5.6 ounces Domestic Shipping: Currently, item can be shipped only within the U.S. and to APO/FPO addresses. For APO/FPO shipments, please check with the manufacturer regarding warranty and support issues. International Shipping: This item is not eligible for international shipping. Learn More UPC: 885460392038 753950002005 Item model number: DRB-00200