OSNA-Cu 58® has been specially developed for cutting purposes. OSNA-Cu 58® is a low-alloyed copper material based on technically oxygen-free copper with added tellurium or sulphur. 9 {7 f& l& l+ }* E8 @" a' x7 aOSNA-Cu 58® is a perfect combination that offers excellent cutting properties and high electrical and thermal conductivity.