The pulley and gear are made from Duraluminum and steel material for lightweight and strength. One cam gear merely weighs 330g and can be used for both Intake & Exhaust side. Tomei cam gear uses sliding type to adjust crank angle. Each notch equals 2 crank degrees and there are 20 notches of adjustability left & right, so that's 40 degrees of adjustment!
Cam gear is sold individually. Please buy 2 for both Intake & Exhaust camshafts.