Made of silicone, attaching the tabs without having to stick the fret to the keys. to remove them without leaving nasty glue stains. There is a double pentatonic display of the notes of each key, which helps to identify the corresponding keys faster. Can remove the note strips easily when you are familiar with the keys and note rules. If you are not so skilled, you can still put it back. For standard size 88 keys piano, you can easily use it on grand piano, upright piano, 88 keys digital piano, practice piano Not compatible with some non-standard 61/54/49/37 keys keyboard instruments, you need to confirm the size of your keyboard. The width of the space between the top of and the keyboard shell must be than 0.2IN(5MM). As many digital pianos have and the case attached together, so when you use this product there will be a problem of not being to lay it flat, but this does not affect your use Material: Silicone colour: Multi-color Package Contents: 1 x Piano Sticker kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.