Efficient Portable Piano Tuner - Lightweight and comfortable. L-shaped design makes it easy to use and convenient to carry. Well made with exact force to tune your piano without damaging the instrument. Suitable for most upright pianos - This L-shaped tuner key grip with nickel-plated metal handle fits the pins of standard 3/16" hitch. The tuning hammer hole size is about 0.65/0.26 inch. They can work on most studs very well. Save your valuable time - If you are a piano lover. Do you often find it difficult to start with a grand piano? These L-shaped piano keys can definitely help you. Helps you simplify all the steps. Save your precious time. L-shaped design - The L-shaped design of the adjustment hammer is more in line with artificial body science.It is more comfortable to hold.Does not cause pain to the hands due to prolonged grip. Material premium and durable - The metal shaft of the tuning key is made of hard steel.Abrasion resistance on, small and exquisite, convenient to carry. Durable enough for long time use.