10" Cold Trap with KF25 Ports10 X 10 KF25 Cold Trap Kit Cold traps are used in vacuum applications where contaminating vapors may be present, and a cold trap is required to assure vapors are condensed before reaching the vacuum pump. They can be used with any pump but are mostly used with rotary vane pumps. Protecting your pump will greatly increase the life of all your seals and internal components it will also assure that a full vacuum is pulled based on the pumps capabilities.