Similar to a baseball counter, you press the counter each time a row is completed .. the counter value will increase by 1. You can also view all Clover Knitting Counter.
Counter is a good size, nice that you can put it on a lanyard. For the price, they should have include one. But, counts up easily, re-sets easily, convenient to keep in the knitting bag. Wouldn't be without it. Great gift for knitters.