These inexpensive cylindrical separating chambers with overhanging lid are available in two sizes. They are used for the plate formats of 200 x 100 and 200 x 50 mm. These separating chambers are very easy to use. Complete gas space saturation is easily and quickly achieved by putting a rolled-up piece of filter paper in the chamber. Only a very small quantity of flow medium is required, by virtue of the plain floor. Another advantage is their limited weight compared to the Standard chambers.