The Stacker unit LB 931 will complete the Mithras LB 940 and TriStar LB 941 multimode plate reader models and the Twinkle LB 970 fluorometer in terms of throughput. These instruments can now be used as a stand alone unit, equipped with the new 25 or 50 plate stacker or can be integrated into the Berthold BUTLER LB 930 or any other robot system.