Have you ever run into a recipe that required you to roll dough to a specific thickness? Do you actually measure, or do you eyeball it and hope for the best?
To be honest, sometimes it doesn't matter all that much. Your cookies will be fine if they're a little to fat or a little too thin. But sometimes a specific thickness is more important, like when you're trying to make 3D cookies that are supposed to fit together. Or if you want multiple batches to be the same thickness.
Not only is it hard to roll dough to a specific thickness, but it's hard to roll it evenly from one edge to the other. And if you do decide to measure your dough, how do you do it? Do you measure the edge, or do you cut into the dough to check how thick it is at the center? Do you cut a cookie, and then check that measurement? Frankly, it's exhausting.
Sure, with a lot of practice, you can probably eyeball that 1/4 inch thickness and get it close enough. Or you can do the sensible thing and cheat. Put training wheels on your rolling pin, if you will.
The Rolling Pin Spacer Bands ($6.99) from Casabella will let you do just that. A set of four pairs of silicone bands in 1/16-, 1/8-, 1/4-, and 1/2-inch thicknesses, they slide onto your rolling pin so you can't roll the dough any thinner than the bands*. It's genius, really.
*If you really put your weight on your rolling, you can compress the spacers a little, but they're pretty dense, so you won't be able to compress them by much.
The silicone bands are dishwasher safe and fit standard (not French) rolling pins from about 2 1/4 inches in diameter to about 3 inches. They stretch to fit, and if they're a little loose on the pin it's fine.
The downside of using them is that the dough itself can't be wider than the space between the bands or you'll start rolling trenches into the dough. But the upside is that if you need the dough reach a specific width, you can set the bands at that width on your rolling pin and automatically restrict its size.
When I was rolling pie dough that needed to be wider than my rolling pin, I used one band on one end of the rolling pin and did my best to keep the pin level. It wasn't absolutely perfect, but it was better than my usual lopsided free-handing.
I found that the thinnest bands—the 1/16-inch— were pretty handy for flatbreads, because I tend to get carried away and roll them way too thin. The spacers kept them at a reasonable—and consistent—thickness.
Disclaimer: Testing samples were provided to Serious Eats.