Industrial Purpose Mixing Valve has pneumatically controlled flap that connects one of the two inlet tubes with the outlet tube via a flat closed housing. The Valve is used in conjunction with hopper or machine loaders. The Valve has the feature that during the conveying time of the hopper loader, the flap switches repeatedly on and off in order to alternately draw in material A or B. The Industrial Purpose Mixing Valve ensures that the layers mix as the material runs out of the hopper loader.