With differential tuning being such an integral part of RC racing setting your diff consistently can mean the difference between making the A-main and getting bumped. Team Associated has introduced a digital measuring device that gives a rating to the diff’s hardness (resistance) that can then be used to compare to other setups and is much more consistent that setting a diff by feel alone. The tool is USB powered (a 5v power source, 2a max, is required) and features a 5-digit LCD display housed in an aluminum body. Three adapters are included with the tool to suit 1/10 7mm wheel nuts as well as pin adapters to test 1/10 and 1/8 differentials directly at the outdrive.
Item #91918 https://www.associatedelectrics.com/news/latest_products/2747-new-factory-team-diff-decoder/