Save state file created by ZSNES, an SNES emulator program for PCs; contains an emulated save state snapshot of the game progress; may be used to save state at any point during gameplay.
ZSNES provides ten save slot files, ZS0 through ZS9. To change the save state slot, use the "Pick State" option under the "Game" menu, or press the "F3" key and use the arrow keys.
NOTE: A ZSNES save state is different than an in-game save state. A game may only allow a user to save state at specific game milestones whereas ZSNES save states can be created at any time during gameplay.