This trap contains oxygen, moisture and hydrocarbons adsorbents in one trap and is packed and purged under helium. The glass indicating trap clearly shows when the filter needs to be replaced with the use of color changes. The packing material is a silica-based environmentally friendly substitute for cobalt dioxide(blue) in the moisture indicator. Available as a kit with the necessary 1/8" brass connectors, and as a replacement trap, this system is easy to install.