... , four grapes output,step-4dBm OEM LMS300 High stable optical light sourcesHandheld PON Stable source LMS-300P , provides 1310nm,1490nm,1550nm wavelength ... or manual on/offTwo AA batteries, easy to changeSpecification PON Stable Laser SourceOutput wavelength(nm)1310nm,1490nm,1550nmEmitter TypeFP-LDOutput Power ... ×45Weight (g)300 PON optical power meter 1550/1310/1490nm with stable laser source