Features: Music theory effortlessly with this learning designed for both kids and adults, for children and professional grade tool for serious learners. The set includes a color LED music ruler, high transparency note charts, and a writable staff board, all crafted from durability, waterproofed plastic for long lasting use in various environments. Ideal for music teachers, auto taught students, and parents seeking interactive educational aid to enhances home or classroom learning experiences. Perfect for mastering scale during practice, analyzing chord progressions in lessons, or quick reviews on the go with its light weight, portable design. Music literacy through color coded visual guides and multi functional tools that bridge sheet music fundamentals to practical instrument applications like guitar accessories. Specifications: Color:Two Choices Dimension:21x10cm/8.26×3.93in 19×10cm/7.48×3.93in Component:Plastic Package Includes: 1pc Music theory ruler note: 1.Please allow 1-2cm errors due to manual measurement, making sure that you will not mind before order. 2.Due to the differences between different monitors, the picture may not reflect the actual color.