This pack contains 6 ink refill cartridges that come with our famous SWAT Pen. These are medium size amazing quality parker style refills that our customers LOVE! They are more robust and contain 20% more ink than other parker refills products. This refill will also fit most brand of tactical pen. <p>We have included a spring that fits your tactical pen. This little spring, so small and easily lost, is quite difficult to find on its own and most people end up buying a new pen... It is in for free!