So I like this tool. Was initially disappointed because it has no instructions and obviously has some slide measurements that are not necessarily intuitive to read. Not in a box, not online. I mainly use this to level the fence on my router table and table saw. Works very well for this as the clasp has a latch. It is made with high precision and has no backlash and is a true 90 degree angle. A bit pricey without instructions but I've made good use of it.