26 STATIONARY AND PORTABLE TESTING SCREENS FOR SIZING TEST SAMPLES OF CRUSHED STONE, SAND AND GRAVEL, SLAG, COAL AND COKE, ORES AND SIMILAR MATERIALS, SAMPLE SPLITTERS FOR PREPARING SAMPLES FOR TEST-SIZING, AND ACCESSORIES AND PARTS THEREOF-NAMELY, SCREEN TRAYS, TRAY RACKS, SAND ATTACHMENTS, DOOR ENCLOSURES, HYDRAULIC AND MECHANICAL CLAMPS, WIRE BRUSHES, CARRYING CASES FOR SCREENS, COVERS AND COVER HOLDERS, AND MATERIAL PANS