What gaming accessories actually improved your skill, not just vibes?

We all buy stuff thinking it’ll magically make us better, but maybe most of it is just… aesthetics. Again, who doesn’t like good vibes? Right!  

However, I’m curious what actually made a noticeable difference for people other than aesthetics. Is it aim, awareness, consistency, or anything else? Not RGB, not desk vibes. 

Genuine question: So, which gaming accessory has enhanced your skills along with your aesthetics?