We designed our gauge to the exact dimensions and then carefully fabricate it from a strong, smooth, polished material for a perfect fit. Your Dual TK-12 cartridge holder will fit easily into our gauge. You'll be able to properly align the cartridge/stylus for optimal tracking and minimal distortion. We've used it in our shop for many years on the hundreds of Duals serviced. If you would like to know whether our gauge will fit your Dual turntable please inquire.
And, if you have any questions regarding how to use the gauge or other questions with setting up your Dual turntable feel free to ask. As longtime trusted and respected Dual turntable service and repair experts we have vast experience with many Dual models and will be happy to assist you. That's something we guarantee other sellers can't do for you.