A couple of minutes to set it up and insert the right tips and I found it pretty easy to open up my Wife's Tag watch to replace the battery. A handy little tool. Unless you are stupid you don't really need any instructions on how to use it, its common sense and easy to use. For the money I think its a bargain. Add the cost of this tool ($15) plus the cost of a new battery from Walgreen's ($5) I ended up saving over $55 on what it would have cost for a watch store to replace the battery. Don't pay these rip-off store prices for battery replacements, just do it yourself and get a tool like this!