Designed for Recurve target archers Includes: Black Eagle M-ST nock Straightness tolerance: +/- .006 Weight tolerance: +/- 2 grains Weight: 500 (8.3 gpi), 600 (7.1 gpi), 700 (6.4 gpi), 800 (6.0 gpi), 900 (5.3 gpi), 1000 (5.1 gpi), 1100 (4.8 gpi), 1200 (5.1 gpi), 1300 (4.9 gpi), 1400 (4.8 gpi)