I'd venture it's something in the Franklin Gothic family, with the capital I used in place of the 1. I'm going to disagree with you there, unless it's a very specific modification of a Franklin Gothic face. Seeing the Broncos playing the Chargers on Monday night renewed my interest in this specific font. Franklin Gothic Book appears to be the closest version (in weight) to what the helmet font looks like. However there are several differences. Franklin Gothic Book: The Helmet Font (1, 2, 3, 5): (8): (7): Besides the difference you pointed out (the 1), the 3 and 5 are noticeably different, and the 8 appears to be two overlapping circles (one on the other) as opposed to a firgure-8 like Franklin Gothic's. Also, on the helmets, the stroke weight for the numbers appears to be even throughout the whole of each character, whereas with Franklin, the weights differ here and there (6 and 9 for instance.) Plus, not pictured is (found a picture) the number 7 which is also a fairly striking difference: the helmet 7 is two straight lines. The larger portion of the Franklin 7 is curved like Helvetica. I've been keeping an eye out for this typeface for a long time. Does anyone have it or a lead as to where I could get it? (Or even rasters of each of the numbers so that I could trace them in Illustrator?)