Screen Trays meet relevant wire cloth specifications of ASTM E 11, AASHTO M 92 or ISO 565, 3310-1. Cloth is designated "S" for plain steel or "SS" for stainless steel. Wire cloth sized for specified machines. Trays with cloth No.16 (1.18mm) and finer use support ribs or coarse backup cloth to support mesh. Backup cloth may be added to trays with or without support ribs. Blank trays (with no cloth) for TS and TM models are available as TSA-136 No.4 and coarser mesh and TSA-137 blank tray for No.5 and finer mesh. For PS models, order PSA-336 Blank Tray without cloth, supports, and shields. Round Hole Sizes for TS and TM models are punched round hole openings in steel plate as used for coal testing (ASTM D 4749) and other special materials. Verification services to ASTM E 11 or ISO 565, 3310-1 Inspection or Calibration Grades are available Screen Trays. For details, see listing for Test Sieve Verification Services.