D'Addario String Height Gauge

"The D'Addario String Height Gauge is an all-in-one tool to help you set up your guitar with the highest possible level of precision. Made of stainless steel, this durable tool helps you easily measure the height of your strings and pickups, neck relief, and other critical measurements. With access to these measurements all in one place, getting your guitar into its best playing form has never been easier.