Review on GESD Universal Telecommunications Engineering Maintenance by Mark Walsh

They shone as bright as my 10mW. Not bright enough for daytime use compared to my other 30mw units. The picture above shows 4 VFLs labeled 30mW. The terminal ones are significantly darker than the two middle ones. The first ones on the left are those of this purchase. The middle two are from different vendors but have the same colored caps and switches. The last one is from the fourth supplier. It doesn't take long to find out. None of these VFLs have either 30mW at the ends or very poor quality emitters. It is painfully obvious that the outermost VFLs are not as bright as the middle two VFLs. But they are all marked 30 mW. All viewfinders are the same distance from the white wall. All had new batteries installed.