The Best Glazing demand for higher energy ratings and environmental specification has never been greater, especially with the BFRC ratings label and the implications for Building Regulations. All Gemini's sealed units are made using the super spacer bar for improved heat retention. Security Built-in not bolted-on At Gemini we believe that to produce an exceptional PVC-U window, door or conservatory outstanding security must be built in from the outset. That’s why we include: High qualirty friction stays and hinges, Siegenia looking mechanisms and Fab & Fix hardware as standard. Quality Manufacture Every Gemini frame is fabricated using state-of-the-art CNC machinery, assuring you not only of our manufacturing quality, but also the cost-effectiveness resulting from use of the most efficient manufacturing methods.