This Savant RT 490 refrigerated vapor trap has a 4L capacity and traps hazardous vapors to prevent pump damage and offers condensation to -90C (-130F). When using freeze dryers, ovens, desiccators, centrifugal or rotary evaporators under vacuum, the vacuum pump must be protected against harmful aqueous acid, alkaline and organic solvent vapors generated during bioresearch operations. Such vapors can damage pump parts and degrade pump oil, increasing the chances of corrosion. Savant vapor traps use mechanical refrigeration to freeze and remove such contaminants before they reach the pump. Mechanical refrigeration eliminates costly and time-consuming preparation and replenishment procedures necessary in dry ice/acetone cooling methods. Use this -90C trap with low-freezing-point organic solvents (such as methanol, ethanol etc). Solvent vapors collect in a removable glass insert (additional cost). that fits into the freezing chamber along with Savants cryocool heat transfer fluid (not included). Vacuum pump required: 76L/min to 283L/min.