Replacement thumbstick base(mechanical/electronic part) for Playstation/Psone (DualShock / Analog Controller), Playstation 2 (DualShock 2), & probably Playstation 3 (Sixaxis & DualShock 3) controllers.
In other words, can be used for any Sony brand brand controller(for PS1, PS2, or probably PS3) with thumbsticks.
The only Sony controller I can think of it, which it couldn't be used for, is the oldest PS1 controllers(which didn't have thumbsticks)

Use these to replace worn or broken thumbstick base.

As you will need to unsolder the old part, & solder this in it's place - this is only recommended for those who have used a soldering iron before.

This is only the base part(as in picture), not the top part(sold seperately).

Might also fit some non-Sony brand controllers, but only if they use identical thumbstick parts to Sony controllers of course.