I have duplicates of all my most used rulers. I keep those in a rigid sided tote so all I have to do is pick it up and go. I trim down an address label to nothing but my name and put that over the brand logo on the ruler. I will share if asked to borrow a ruler in class but I don't offer. Too many don't buy the recommended tools for class thinking they will use others. I've lost too many tools by sharing in classes/workshops. Quilters should buy the tools they will need even if they only plan to use it once or don't take the class. I understand forgetting to bring a tool, that happens to all of us.