A must-when the castor and camber angles are changed or whenever the geometry of the car is set up you will require these bushes. They are good for cars with up to 3.5 degrees of castor angle.
From November 2003 they have been made from a specially made and cooled consistant rubber compound with an angled centre to compensate for the increased leverage on the lower arms whenever the geometry is adjusted/corrected or increased on castor angles. The normal bushes try to take hence the failure of the standard or moly type bushes available on the market. Always periodically check the locknut on the lower arm pin that holds these bushes. Many racers drill a plain nut and enter a split pin.