Medeco X4 Key Medeco is committed to attaining the highest level of transparency which is becoming increasingly important to facility owners and end-users. To that end, Medeco is now certified by GreenCircle Certified, LLC on multiple products through Multi-Attribute Certification. GreenCircle Certified, LLC, is the leading certifier of sustainability claims in products and operations. Below, the Certified Environmental Facts (CEF) label details the environmental impact data for the Medeco X4 Key. Much like a nutrition label, the CEF label details all necessary environmental information in a straightforward, easy to read manner. The CEF label highlights product attributes as well as sustainable advances in manufacturing.