Hey Genius Crowd! You spoke and we listened. Following the 4th rule of Zen design- simplify, we are proud to introduce Genius EVOLUTION sliding cover. A simple change to our Classic Genius slider offers a lot of options. - Increased bowl size and improved airflow. Once the round opening is over the bowl the sliding cover adds more depth to the bowl. This also slightly changes the bowl configuration allowing for better airflow, which in turn will promote cleaner burning of the contents of your bowl and gives your pipe an overall better efficiency. - Easy access to the bowl. You can now switch between the two different openings depending on how much of the bowl you want to burn at once. Choose the smaller one to burn just a part of your bowl and conserve the contents or choose the larger opening to expose the entire bowl. Also, no more need to remove the cover in the crowded places to check what's left in your bowl. - Easy packing. No more need to remove the cover to be able to pack your bowl. Just slide the cover forward revealing the bowl, pack and slide the cover back to close and stow away. We hope you'll like our new cover as much as we do. And as always we welcome your response!