Copper Turbo Nut Kit M8 x 1.25mm AF8059-1002Copper Turbo Nut Kit M8 x 1. 25mm5 Pack AF8059 1002 8059 1002 Copper Nuts for Turbo Studs. These copper locking nuts from Aeroflow are used in conjunction with our exhaust studs. The lock nut is just like a standard nut, but it has the added function of locking itself to the stud (thread). The main benefit of using lock nuts is once installed the chances of it working itself loose are greatly reduced. Copper Nuts to suit M8 x 1. 25mm Studs, Pack of 5.