All Obv 2's have a flatter, not rounded chin/throat, and usually has an easily identifiable dimple or crease in it. Also the truncation of the neck (where it comes to a tip, will always point directly above the bead exactly above the C in Canada. Obv 2's will have the truncation end to the left of the bead above the C in the gap and more pointed to the next bead left. This is true of all Obv 2's, even the Obv2/1's. You can tell at an arm's length the difference between a 1 and a 2 by looking at the throat/chin shape .. just look at an 1876 and compare it to any Obv 2 from '82, 84, 86, 87, etc.