The S3 lasers (Arctic, Krypton, Lunar, Inferno) have variable power modes. While operating the laser, keeping the Smartswitch pressed will gradually cycle the laser from low power to full power mode.
With the latest model (lightning icon) the LED indicator will show it is at low, medium or full power mode.
The laser will operate at 15% at low, 50% at medium and 100% at full power.
This is the same for all Spyder 3 lasers like the Krypton, Inferno and Lunar lasers.