After fitting the washer to a filter flask, an inverted sample tube is inserted into the washer and solvent is introduced into the reservoir using a series of wash bottles. You can perform numerous wash steps and finish by pulling air through the tube to complete the procedure.
Filter flasks are ordered separately. The single tube washers (WG-1207-series) require flasks with vacuum side arms; LG-7800-102,104 or 106.