Are you sure that your signal conditioners are performing properly? You need to be sure because a signal conditioner is a vital "link in your data chain". You need to know if your signal conditioners are still performing as they were the day they were unpacked from the factory. Older signal conditioners, especially 10 years and older, can drift off of any recalibration quickly.All of Dataforth's signal conditioners ship to you with a TEST DATA SHEET. This factory record is serialized, dated, and tied to the serialized signal conditioner! It is THE Dataforth record of performance. In other words, it is a baseline reference for any future calibration check and it is the paper trail necessary for your own ISO 9001 certifications.As with any quality instrument you purchase, you should receive a calibration certificate. Dataforth believes your signal conditioners should receive the same NIST* traceable calibration certificate. And we provide this TEST REPORT certification free of charge! More than you'd expect - low cost and high performance! Dataforth's TEST REPORT is evidence to its conservative designs and published performance specifications. For good reasons, Dataforth proudly refers to its signal conditioners as "Instrument Class(tm)" products. See for yourself... Online Search for Test Report Datasheets by Serial Number A sample of Dataforth's TEST REPORT (39KB pdf) * NIST - National Institute of Standards and Technology Please feel free to contact our applications engineers at firstname.lastname@example.org should you need any product selection assistance.