I bought the book there 2 days. I have already finished. It is very well done: there is no model, it's a kind of learning or survival guide for overlock and recouvreuses. What dramatize these machines! I have 3 years a bottom cover J **** e, and despite the instructions, I did not dare throw me before this morning. I was stupid of me not to be served earlier! This book is to put all hands to those who are new or are planning to acquire a serger, a bottom cover or a serger cover. Thanks to him, I'm going to use my machines at full capacity (with the help of their manual too!)