Sophia Drop Tuner with Macro-tuner Upgrade Factory Exchange 

Sophia Drop Tuner is a quick tuning lever add-on to the 2:22 or 2:92 Macro-tuners...

Easily change from from one pre-determined pitch to another and back almost on-the-fly, say E on the 6th string to D with a flip of the lever -- flip back for return to E .... easy.

Factory Exchange Upgrade replaces a customer's Macro-tuner with a Drop Tuner equipped Macro-tuner.

Setup with the Global Tuner Pro, Stabilizers Plates or StopBlock with TremStop.