【FitFlight】PRO D-4 D black 's Japan Review

I bought it thinking it would be between S-4 and V-4.
D-3 seems to be the standard for teardrops, but I chose D-4, which has a slightly wider area.
I enjoy changing the settings depending on my mood, etc. (I can still feel the difference in the settings.
(I am not yet good enough to feel the difference in setting...)