Pressing the SELECT button will cycle through all the possible scale choices on the Palm Abbe Digital Handheld Refractometer. If you want to permanently change the refractometer scales, you may send it back to us and we will be happy to reprogram it for you for a slight charge.

For more information about refractometer care, maintenance, and troubleshooting, please see the following MISCO page: Digital Handheld Refractometer Training.