actually serum.... the gen II and the III used the brass idlers.....gen I where just the gears and the shift dog w/ ue idlers...but everything was hard anadized teflon coated (i think that what Dan used).....I was one of the testers for the Gen II gears....and then after that Dan made another improvement and added the steel pins..for a steel-to-steel contact......if you dont belive I was a tester goto this link....I'm on the bottom of the page...
http://www.thewebmine.com/testimonials.htm