The Validate heparin calibration verification and linearity test kit from LGC Maine Standards, Cumberland Foreside, Me, has received FDA premarket notification (510(k)) clearance for use on Instrumentation Laboratory ACL Top 500 hemostasis test systems. The kit evaluates heparin anti-Xa activity in a human plasma matrix. Each kit is prepared using the ‘equal delta’ method for linearity testing recommended by the Clinical and Laboratory Standards Institute, and is liquid, ready-to-use. Users add the product from the dropper bottle directly into a sample cup and run in replicates. The kit enables clinical laboratories using Instrumentation Laboratory ACL Top 500 hemostasis test systems to complete their required heparin calibration verification and linearity testing, and maximize the reportable range while minimizing manual dilutions. For more information, visit LGC Maine Standards.