These Hosco Neck Mounting Ferrules are used in place of neck plates when attaching necks to guitar bodies with contoured heels (like the Ibanez AANJ used on most of their RG guitars). Carved heels are great for playing comfort at the high frets but means flat neck plates can no longer be used, neck ferrules act like large washers to help spread the pressure of the neck screws over a wider area to ensure a secure connection just like a neck plate. These have a flat bottom and countersunk top for countersunk neck mounting screws. Priced per single ferrule.