A lead-free formula for screws and bolts in very hot environments up to 1100 Celsius or corrosive environments. When metal makes contact with other metal, such as titanium and aluminum, corrosion occurs. But if you apply Muc-Off's Copper Compound before assembling parts, situations where, for example, you can no longer loosen a screw will be a thing of the past. Safe to use on metal and rubber. Apply it to, for example, the bottom bracket, threads, bolts and nuts, and the seat post.