... button,2*AAA battery. Popular portable laser Good quality,low price,long lifetime. Product name:Green Laser Pen Model no.JL-006 Dimension ... :black. Battery:2*"AAA" (included). Output Wavelength:532 nm Laser Type:Visible laser Diode. Output mode:constant wave. Output Power:1mW-200mW ... the military,medical and astronomy,indicator, teaching baton 100mW Green Laser