Elevator Grab
From A complete guide to Super Metroid speedrunning
Elevators can be tricky to activate quickly; however, this task is made easier by stopping on a dime on top of the elevator platform, then pressing up or down to activate it.
As the video demonstrates, Samus will be able to activate elevators when one pixel of the ten-pixel-wide bottom of her hitbox is making contact with the elevator pad; however, if all ten pixels are not making contact with the elevator pad, there will be a 50% chance that the input performed to activate the elevator pad will fail.
