Keep unused PTX12K power module positions covered with this Juniper PSM blank. In dense routing platforms, open bays are more than cosmetic; they can affect airflow paths, expose internal components, and complicate service routines. A properly fitted blank helps maintain the physical integrity of the chassis while supporting a cleaner, more controlled installation. For teams building out PTX12K systems in phases, blanks are a practical part of the deployment plan. They help preserve the intended airflow pattern when not every slot is populated, and they reduce the chance of accidental contact or contamination in open positions. That matters in environments where uptime, thermal consistency, and serviceability are all part of the operating standard. This is the kind of accessory that disappears into the system when installed correctly, which is exactly the point. It supports a more disciplined rack presentation and helps keep the platform ready for future expansion without leaving gaps in the chassis.