--- title: NoOneMakesYouSmarter description: No one makes you smarter. 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QuadraTherm 640i with qMix is like no other thermal flow meter on the market. It delivers the data you need for smarter decisions, with unmatched accuracy. ##### Highest Accuracy Achieve the highest flow meter accuracy (+/- 0.5% of reading) ##### 100% Field Configurable Change gases & compositions, add multiple full scales, and adjust pipe size ##### User-Friendly Software Use qMix™ software to easily create pure gases or gas mixtures in the field and retain accuracy - no recal needed ![Desktop Image 2](https://info.sierrainstruments.com/hubfs/Desktop%20Image%202.png "Desktop Image 2") ![quadratherm_pdf_thumbnail_high](https://info.sierrainstruments.com/hubfs/quadratherm_pdf_thumbnail_high.png "quadratherm_pdf_thumbnail_high") #### Learn 5 Ways You Can Revolutionize Your Process Discover five ways QuadraTherm helps improve your process efficiency and makes you and your process smarter in our detailed guide. DOWNLOAD FREE GUIDE ### Have questions or need a quote? 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