Pretty hard to mess up rubber bands....they stretch they are rubber and they are in the shape of a band. Oh and you can use them to shoot at people if you launch it off your index finger. Also...why the extra 5?
I'm used to rubber bands at my insurance company job. Yours are about the same size but are noticeably too thin. I don"t feel like I can trust them to hold my folders and papers for long. `Even on general home use they are too weak.