Fisher Space Pen Zombie Apocalypse Cartridge Space Pen (W375ZA) The cap for this exciting New space pen W375ZA is an actual 375 H & H mag shell. The raw brass bullet Cartridge is plated with nickel silver and the portion of the pen that contains our PR Cartridge (pressurized refill) is a highly reflective chrome. Writes at any angle, even in Zero Gravity. Simply the most versatile pen ever made. Each Fisher Space Pen is precision assembled, hand tested, and carries a lifetime guarantee against all manufacturing defects Each Fisher Space Pen is precision assembled in the USA, hand tested, and carries an unconditional lifetime guarantee. All brass and steel construction.