So I'm a big handyman who sells a lot of stuff and I've always folded my shirts in half. Well, that's enough for me because no matter how careful you are, there's always that shirt that's the last thing in your stash that you're going to ruin. These guides really make it easier and easier to get perfectly trued. I wear a lot of baseball style shirts with ¾ sleeves and they're hard to center, but these guides make it so much easier. Just make sure you line it up correctly and you should be fine. You get 5 sizes for different ages plus an extra tape measure. They are made of good PVC plastic so they will last a long time. Worth every penny!