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 most upright pianos. standard 3/16" hitch pins. The tuning hammer hole size is about 0.65cm / 0.26inch. They can work on most uprights very well.Save your valuable time - If you are a piano lover. Do you often have trouble getting started 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. Doesn't cause pain to hands due to sticking for a long time.Premium and durable material - The metal shaft of the tuning key is made of hard steel. Abrasion resistance, small and exquisite, convenient to carry. Durable enough for long time use. Features: 3 Pack a Set Come with 3 adjustment wrenches. Enough for your replacement in daily life. Or you can also share with your friends. Handy tuning hammer Specially designed for tuning guzheng and most small machines with quadrilateral openings.</ p> Lightweight and portable The key is a little shorter than the professional key, which will not affect the result of using, just need more strength to do it. use. Specifications: Material: Steel and Plastic Inner Bore Size: Approx. 0.65cm / 0.26inch Total length: approx. 15.5cm / 6.1inch Handle Length: Approx. 10.5cm / 4.13inch Weight: 78g per unit Note: Please measure the tip size of your device before purchasing, make sure your devices size matches the quadrilateral of the key. Package includes: 3 x square shape piano tuner key