Steel, sae 8615, 2.198 in. Min, 2.208 in. Max lg, 0.725 in. Min, 0.735 in. Max diameter of ends, 0.615 in. Min, 0.635 in. Max diameter center, 2 holes 0.294 in. Min, 0.303 in. Max dia, holes 0.216 in. Min, 0.226 in. Max from end of link, holes must be in line and on center whitin 0.005 in