About this 3D model
Here is a replacement batter compartment covering panel for the Nerf Stryfe. This allows the extra space required to install a 9V battery in the existing battery compartment. This part is designed to print without supports. My blog shows the other modifications required to connect a 9V battery: http://teslaandi.wordpress.com/2014/07/12/nerf-stryfe-9v-modification/