--- title: PH Tool Reference Standards Blog description: PH Tool Reference Standards Blog --- [![PH Tool | PH Tool Reference Standards - The Standard of Excellence](https://content.phtool.com/hubfs/Phtool%20November2017/images/logo.png)](https://www.phtool.com/) [Order Online](http://www.phtool.com/store2/) [267-203-1600](tel:2672031600) - [Select Language](https://customers.phtool.com/language/) - [English](https://customers.phtool.com/) - [Deutsch](https://customers.phtool.com/language/deutsch/) - [Chinese](https://customers.phtool.com/language/chinese/) - [Français](https://customers.phtool.com/language/francais/) - [Dutch](https://customers.phtool.com/language/dutch/) - [Italiano](https://customers.phtool.com/language/italiano/) - [Japanese](https://customers.phtool.com/language/japanese/) - [Korean](https://customers.phtool.com/language/korean/) - [Portuguese](https://customers.phtool.com/language/portuguese/) - [Español](https://customers.phtool.com/language/espanol/) - [Taiwan](https://customers.phtool.com/language/taiwan/) - 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(1)](https://content.phtool.com/blog/tag/what-is-edm) - [phased array ultrasonic testing (1)](https://content.phtool.com/blog/tag/phased-array-ultrasonic-testing) see all - [Home](https://customers.phtool.com/) - [Shop Online](http://www.phtool.com/store2/) - [About](https://customers.phtool.com/about/) - [Standard Test Blocks](https://customers.phtool.com/shop-standard-test-blocks/) - [Reference Standards](https://customers.phtool.com/custom-reference-standards/) - [Flat Bottom & Other Types of Holes](https://customers.phtool.com/flat-bottom-and-other-types-of-holes/) - [Gauges](https://customers.phtool.com/precision-mechanical-gauges/) - [Resources](https://customers.phtool.com/resources/) - [Contact](https://customers.phtool.com/contact/) ![Phtool](https://content.phtool.com/hubfs/Phtool%20November2017/images/logo-footer.png) 6021 Easton Road Pipersville, PA 18947 [267-203-1600](tel:2672031600) ![ASNT Corporate Partner](https://content.phtool.com/hubfs/Phtool%20November2017/images/asnt.png) Corporate Partner - - - - Copyright © 2026 phtool.com Website Design by IQnection - A Digital Marketing Agency