Maintenance involves only occasionally replacing the batteries. The SP-3 operates on 2 very efficient lithium cells. To replace them, remove the blue end plug on the bottom of the light, slide out the flexible orange end plug and tap the open end of the light against your palm so that the batteries fall out.
Then take 2 new cells, hold them together, "+" to "-" and insert them, following the polarity arrows. If the batteries are accidentally inserted backwards, it will not harm the SP-3. Check that the SP-3 is operating correctly, then replace the flexible rubber plug and, last, insert the solid plug firmly into the rubber plug.
