These machine head feature internal sealed gears to infiltration, while included mounting screws / ferrules ensures do not need tool installation on most guitar models Maintain consistent string tension during live, studio recordings, or practice with these guitar tuning pegs The oversized square knobs provide enhancing grip for smooth adjustments, while the sealed construction ensures long lasting even in humid environment Ideal for professional musicians, guitar technicians, and enthusiasts seeking tuning hardware replacements or upgrades for their instruments Upgrade your acoustic or electric guitar with sealed guitar tuner pegs, crafted from metal for precise ratio tuning stability and resistant finish