... developing optical communication measuring instrument, we are familiar with high quality&efficiency requirement.OTDR EG6818 High Performance&Multifunction ... ,one-button operating ο Test up to four wavelengths with a single unit ο Communication light check automatically ο Remote function via ... in single unit, such as 850, 1300, 1310, 1383, 1490, 1550, 1625 and 1650nm wavelengths, with which EG6818 ...