On and Off Barrels are a type of barrels found in Donkey Kong Country. They appear as floating barrels with either the word "ON" or "OFF" written on them.
These barrels only appear in one level, Loopy Lights. If the respective barrel is set on the word 'OFF', all the mine shaft lights in the level are turned off; but if the player (Donkey or Diddy) touches one and the word 'OFF' on the barrel will be changed to 'ON' meaning the lights will be turned on, allowing the player to see the level more clearly. Noticeably, the red Klaptraps cannot be seen very well when the lights are turned off, so the player must be cautious. Stop and Go Barrels from the same game work similarly to On and Off Barrels.
Numerous barrels that function just like On and Off Barrels from Donkey Kong Country appear in Glimmer's Galleon, a pitch-dark underwater stage from Donkey Kong Land 2. However, instead of the words "ON" or "OFF", they display a small light bulb icon. Once touched, the barrels will light up the area temporarily.