The Plate Mate protects your guitar's bridge plate from damage caused by ball-end strings and enhances your tone too! Brass plate installs in minutes with no tools required, held in place by the strings' ball-ends or with supplied two-sided tape. The Plate Mate can also be used to protect from further damage bridge plates that are already eroded, but not yet cracked. Staggered with the 1st bass string hole farther from the neck as on Martin instruments.