The latest Tech Tuesday with Profile:

"One of the most common tech questions we get asked: what sprocket hat washers work with what sprockets? Profile offers only two traditional bolt-on sprockets: By bolt-on, we mean Non-Spline driven sprockets that take a spider/crank arm fixing bolt to attach it to either a Right Hand or Left Hand Drive crank arm. In this video, we go over the Profile Imperial (19mm only) and Profile Blackjack (19mm or 22mm). The Profile Sabre sprocket is another bolt-on alternative; but it takes a universal insert rather than a hat washer. You can check out more info on the Sabre options HERE."