Focus Purple Laser Flashlight

Specification:Wavelength :405nmMaterial :AluminumSurface treatment:black anodizedOn-off mode:touching switchBattery :16340 rechargeable batteryWorking voltage:DC3.7VDimensions :phi23 x 150mmCan light a matchSize: 133(H)*33(D)mmPacking list:.1x adjustable focus purple laser flashlight.1x rechargeable battery.1x key How to burn a match?let it shoot on the surface of deep color's object or black object between 100mm to 150mm after opening the laser flashlight,then turn the screw to right with the smallest focal pointer that it's more easy to burn match within a short time.