I have a bunch of various tuners from over the years in different horn cases, but the one I prefer now is the small clip-on polytuner by TC Electronic.

https://www.sweetwater.com/store/detail/PolyTuneClip


BIAB 2024 Win Audiophile. Software: Studio One 6.5 Pro, Swam horns, Acoustica-7, Notion 6; Win 11 Home. Hardware: Intel i9, 32 Gb; Roland Integra-7, Presonus Studio 192, Presonus Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors