Features: Efficient way of setting a temperament -- used to mute two octaves at once by pushing between the groups of strings with a screwdriver or flattened hammer shank. The piano tuning wrench of L-shape design features exquisite appearance and easy operation. Package comes with 1 wrench hammer, 2 rubber mutes with handle, 2 rubber mutes, 1 felt temperament strip and 1 bag of felt temperament circles (appr. 90ocs) to fully meet your needs. Made of high-quality professional materials, the tools fit for the piano tune perfectly. The rubber mutes have a centain flexibility and abrasion performance in order to reduce the abrasion on iano parts and be reused for many times. Indispensable tool kits for piano players to do piano tuning work. Specifications: Material: Wool Felt+ Rubber+ Metal Color: Red Item Size: Felt Temperament Strip Length: 108cm / 42.52in Felt Temperament Strip Width: 1.3cm~2.3cm / 0.51in~0.9in Felt Temperament Strip Thickness: 0.5cm / 0.2in Rubber Mutes (without handle) Size: 10.2 * 1.3 * 1cm / 4 * 0.51 * 0.39in Rubber Mutes (with handle) Size: 4.7 * 1.1 * 1cm / 1.85 * 0.43 * 0.39in Felt Temperament Circle Diameter: 1.2cm / 0.47in Package Size: 18 * 15 * 4cm / 7.1 * 5.9 * 1.57in Package Weight: 143g / 5oz Package List: 1 * Wrench hammer 2 * Rubber mutes with handle 2 * Rubber mutes 1 * Felt temperament strip 90 * Felt temperament circles