https://www.gbic-shop.de/de/produkte/transceiver/sfp/kompatibel-6/1000base-sx/sophos-asg0000sx-detail.html High-quality ICs (such as Maxim Integrated or Netlogic) and therefore have the same quality or even a better quality as the original Sophos ASG0000LX 1000Base-LX SFP Transceivers, depending on the manufacturer.