Key Full Size - The piano keyboard contains 88 full keys, which can cover a keyboard or a piano with 88 keys. Piano Keyboard Assistant only works with 88-key keyboard pianos, electronic keyboard pianos, electronic organs. You don't need to know the names of the keys or where middle C is, just place the note strips on the piano keyboard. Material advantages - Piano keyboard notes guide is made of a softer and more environmentally friendly silicone material. Easy to install, Easy to remove, without leaving any residue, ready to use, and keeping your keyboard clean and tidy. Book clip is made of quality stainless steel, won't rust or corrode and won't easily bend or get misshapen. Smooth finish to not damage to books.