I bought a "scoop" a number of years ago to make my traditional raisin cookies for Christmas every year. You grind up an entire box (15 oz.) of raisins to mix into the dough, so you can see it is very sticky. This was before I had heard of King Arthur. I went to the local restaurant supply. There these scoops are called "dishers".
The number refers to how many scoops make a quart. There's a chart showing the sizes and how much each holds here:
http://www.chefs-resources.com/Scoop-DisherSizes
April 4, 2015 at 12:13am