Gamma Sports String Things Vibration Dampener (Tennis Ball/Brain) - Walmart.com
I've been playing this thing for the last few years, it's gone through several grips and string sets. I was told it looks like I play a waffle iron : r/10s
String Thing USA
String Thing Tennis String Straightening Device - W & D Strings
How to String a Tennis Racquet: 13 Steps (with Pictures) - wikiHow
How to String a Tennis Racquet: 13 Steps (with Pictures) - wikiHow
Tips and Gear for Tennis Beginners
Natural gut tennis racket strings: The history, myths and why it's the best