Review on Improved Joystick Thumb Stick Key Caps for enhanced gaming experience on Sony PlayStation: Hapurs Anti-skip Silicone Replacement Joy Stick Controller Shell Cover Protector for PlayStation 3, PS4, and Xbox 360 by Kevin Staniszewski

Improves joystick feel. For me, the PS4 joysticks were a bit small for my big fingers. They also have a thumb notch, but I find this keeps my thumb from rotating on the joystick. I have to be able to do that in order to be able to make precise movements in shooter games. That's where these grips come in. The rounded grip is reminiscent of the old PS3 controller. Try it, you will notice the difference.