Enhance your musical experience with this four- knurled head screw for alto and tenor horns. Designed for easy installation and , it provides a reliable solution for maintaining your instrument's alignment. This accessory is a must-have for musicians seeking to their instrument's performance and durability. Features -Color:Golden -Material:Metal -Size:0.79X0.79X0.65cm/0.31X0.31X0.26in -Stable performance: the horn knurled cap screw design ensures that the keys stay secure and do not loosen, enhancing the stability of your performance -Reduced noise: the triple flat structure is to effectively minimize noise, delivering a purer musical experience - horn compatibility: specifically designed for horns with four keys, it provides a and easily your instrument's performance -Simple installation: the upper bass horn fixing nut allows for easy installation and quick adjustments, accommodating various performance needs - quality: this instrument accessory is crafted for durability, ensuring it enhances your performance for years to come Package list: 1 x french horn rotor screw