Ideal for use with all ball bearing turbochargers. These great little restrictors restrict the oil flow/pressure to the core of the turbo to ensure long life of your seals. They suit -3AN and -4AN 200 series steel or stainless-steel fittings ONLY. If you are using our aluminium fitting it MUST be installed into an adapter fitting with a 37-degree male end. Recommended for use in all Boosted ball bearing turbochargers. They feature a 1mm (3/64") internal hole and sold as a pack of ten.