With the magnet wooden sound wave designs, I find that it works best to use only one to three words with a maximum of 20 wooden slats instead of using longer phrases to avoid damage such as cracking or breaking. I use a neodymium magnet that is placed on the back of each piece to guarantee a strong and lasting hold. The magnet designs can depict the sound wave of your choice with or without a background. You can also choose to have the word(s) or phrase you selected to be shown on the front of the sound wave magnet, in the background, or on the back.