The new CTO-40S Slim Line column oven is ideal for saving space while maintaining excellent thermal stability. The new built-in dual leak sensors can detect small leakages of the mobile phase. Warming up the sample band and mobile phase in the column inlet tubing to match the set oven temperature is possible with an optional preheating system. A switching valve can be installed for 2-column selction, and an additional valve can be added at the top of the oven for diverting flow to and away from an MS source.