Clutch Kit, for, BMW M50, M52, S50, S52 engines with bwm gettrag and zf gearboxes combination. The one piece billet flywheel is made of Chrome Moly steel and we are using Tilton OT II twin or triple plate clutches for power from (900nm-1500nm). The weight of flywheel is 4.7 KG The full kit weight is around 12kg. Please let us know what power and wich gearbox are you using when ordering.