The hopper sits on top of the gold cube and fills with water. Using the steel classifier material can be classified directly into the hopper where the material flows into the gold cube. Classifying and sluicing is completed in one step. Hand welded at our shop. 
 
Hopper, classifier and levelling stand are included. No pumps or hoses are included but the 1100gph pump that comes with the gold cube will work as well as the hose.