Counting chambers Sedgewick Rafter, without grid

made of glass, with cover glass. For many applications, particularly for some APHA methods and where larger plankton are being analysed, there is no requirement for a counting grid printed onto the slide. This is where the Sedgewick Rafter counting chamber with the plain glass base is deployed. This chamber is suitable for either upright or inverted microscopes. It can be used in conjunction with an eyepiece reticle, such as the Whippie micrometer disc.