The innovative Sunderland mk1 pen manufactured from 6061 aluminum and 17-4 stainless steel and plated in electroless nickel.
Each nickel mk1 is hand polished to a high luster.
Note that the nickel will patina slightly over time. Some users like the patina, while others prefer to maintain the bright polish. Any mild metal polish such as Simichrome or Flitz will easily return the pen to as-new luster.