Hey all, I’m happy to share a small plugin I recently developed for UCSF ChimeraX: Cube’n Tube. It extends the standard eraser sphere tool. Instead of only a sphere, you can now erase with cubes, cylinders (frustum), cones, or even define your own custom shape. While working with various protein structures, I often felt that a spherical eraser is not always ideal. Especially when trying to remove part of a filament, micelle density, or isolate one asymmetric unit of a larger assembly. I was really missing a more dynamic eraser tool, so I decided to build it. I also implemented a simple undo/redo function for the eraser tool. I cannot count how often I misclicked and had to restart my masking from zero… Now there is a one-step undo (limited to one step to keep it smooth on all machines). The custom shape option works particularly well together with a fitted atomic model (for example from AlphaFold) to erase everything outside the region of interest. Cube’n Tube can be downloaded directly from the ChimeraX Tool Shed or from GitHub (https://github.com/TaminoCairoli/CubeNTube) If you are missing a feature or have ideas for improvements, feel free to open an issue on GitHub. Many thanks to the team (especially Tom Goddard) at University of California, San Francisco for building such a powerful and well-documented tool, and thanks to Pavel Afanasyev, Julius Rabl and Dianhong Wang for discussion and testing. Best, Tamino