These tactile switches for the Game Boy Advance SP are great for modders on a budget who are looking to improve the feeling of their GBA SP's L and R triggers.
Higher-quality clicky tactile switches are also available.
The switches only have 2 posts to solder whereas the original switches have a metal frame for support (4 posts). I ended up using the RM clicky switches instead.
Essentially the exact same as the original Nintendo piece that needed replacing, no complaints about the performance. You buy a button, you get a button.
Had to bend the contacts into shape to put in the through-holes, though.