As my name suggests, they fit Stadia Controllers. They are made of pleasantly soft rubber. I got them because I've been using control freaks for years, but the Stadia controller's joystick is just a hair smaller than the PS4's, but not as small as the Xbox's (I've got them all, including a PC with a GeForce 1070 ). So the control freaks worked. on the Stadia Controller, but they moved and rotated easily, so it was annoying. Anyway, I got them, installing them on a Stadia controller was a bit easier than a PS4 controller, but they don't budge on either of them and work fine. To simply place them on the stand above the controllers, spread the rubber with your fingers and once they're half stretched gently push down and twist, it sounds easier than it is but that's the point. I will update if I have trouble taking them off. Note: Not to mention the thumb grips, I mostly play on my PS4 because all my friends have one. I play Destiny 2 and Apex Legends, that's all. Don't let these reviewers dissuade you from buying Stadia, it works great, I don't see any difference, Destiny 2 has no input lag and runs much smoother on Stadia at 60fps. Maybe I have a great internet connection (Frontier Fios) and I'm connected, but I really think it's just a bunch of fanboy haters. I don't care what console I play on, as long as I'm having fun.
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