Goldline Digital Handheld Salt Meter w/ Calibration Solution. This salt meter is completely waterproof and comes in a convenient case for easy storage. The tester is built with an auto-shut off feature and is battery operated for easy use and set up Using a Digital Saltwater Meter is the best way to accurately and quickly test the salinity of your pool water. Salt water chlorinators will often give you an incorrect salt reading due to a circuit board error or a dirty cell. This can cause pool owners to add salt without double checking first which usually results in an pool with too much salt that could require draining. NOTE: Hayward has changed the design of their digital salt tester. While supplies last, customers may receive the existing style. The blue colored tester is very new as of late 2016, and may not be available in all locations. Both the existing green as well as new blue versions have the exact same part number.