I had been looking for a tape measure that had metric measurements on it as I am a science teacher and my father-in-law was raving about how much easier some project was when he used his metric square. This tape measure has a nice hefty feel to it--it does not feel like a toy. There are two ways to lock the tape in place; a button underneath for a temporary hold, like laying the tape measure down and a permanent hold with the slide button. The write on feature is a boon when working by oneself and you don't want to write on the project, just be sure to use an erasable pen or pencil. The built-in pencil sharpener is handy as well; even my kids will go out to the garage when they can't find their personal pencil sharpener.