60 Day 100% money back guarantee. Precision VLSI Standards Inc. model SHS-24.0 QC quartz step-height block. Nominal 24 µm (0.024 mm) vertical step etched into a 1 × 1 in substrate for verifying stylus, optical, or interferometric profilometers. Surfaces show light handling marks only; edge integrity is intact. Includes original acrylic storage cube with matching ID labels. Calibration status is unknown and the unit is sold as-is for metrology labs that perform their own traceability or use it for training and setup checks. Ideal for AFM, WLI, confocal, and SEM workflows that need a mid-range height reference. Keyword Block: vlsi standards, step height standard, shs 24.0 qc, 24 micron, quartz calibration block, profilometer reference, metrology gauge, surface measurement Data Sheet: https://www.vlsistandards.com/pdf/products/Dimensional/SHS.pdf