Thermo Scientific&trade;&nbsp;Sliding Drawer Racks for Tubes (4 inner door freezers) For 900 Series 28CF, TSE600 ULTs, Boxes per Rack: 28, Compatible with Matrix 1.0mL 2D (Mfr. No. 3740 to 3742) Thermo Scientific&trade;&nbsp;Sliding Drawer Racks for Tubes (4 inner door freezers)