If you have slow windows and/or windows that fall off centre when raising and lowering the glass its likely due to the original bush that often wears down causing the window to lean on the side of the window guide as opposed to nicely rolling up the channel (you may even find it's not there at all and is sitting at the bottom of your door)
Genuine Mazda replacement part
ONLY 1 BUSH IS REQUIRED PER WINDOW
Suits all NA/NB 1989-2004