Gold Tone BGT Chromatic Tuner - Includes Clip-On Mic parts this is the one you

this is the one you would probably want

and strap button installation

Beard EBS-17 Spider Bridge Insert - Maple/Ebony Slotted

a bone nut

and no need to drill a hole through the banjo's rim

Gold Tone BGT Chromatic Tuner - Includes Clip-On Mic parts this is the one youQuickly and accurately tunes your instrument! This tuner is designed to hone in on the specific note being played and ignoring overtones. It is designed to find the note quickly and not jump around like some tuners. Multiply settings including chromatic, 5 string banjo, guitar, and mandolin fiddle Designed for use with bluegrass instruments Includes a clip for isolating your instrument alone, making tuning in a noisy environment much easier