Hey Everyone! I've gotten a few PM's from members trying to follow this guide and are S-ON about how to fastboot flash a kernel when it isn't packaged into a boot.img for you. A good example of this is the arc reactor kernel: [Kernel][JB][SENSE] Arc-Reactor [3.4.40][S2W][linaro] [-O3][WIP] - xda-developers When you download and extract the kernel you'll notice there is no boot.img! However, the kernel is located inside of /kernel. The zImage is the output of the compiler when you build a kernel from source. In order to flash that zImage, you'll need to incorporate it into the boot.img along with the proper ramdisk. Step One: Download your files Get the Android Image Kitchen: [DEV][TOOL] Android Image Kitchen - Unpack/Repack Kernel/Recovery + ramdisk [Win32] - xda-developers Arc Reactor Kernel (MikMik): [Kernel][JB][SENSE] Arc-Reactor [3.4.40][S2W][linaro] [-O3][WIP] - theMikMik Dev-Host: Dev-Host - The Ultimate Free File Hosting / File Sharing Service Stock boot.img for your ROM Step 2: Extract the 2 zip files Its also a good idea to place them somewhere convenient (I just do the desktop) Step 3: Move the stock boot.img into the folder for the Android Image Kitchen Step 4: Drag the boot.img onto unpackimg.bat This unpackages the boot.img into the split_img and ramdisk folders. Step 5:Inside of the split_img folder, youll see boot.img-zImage...remove or delete it from the folder. Step 6: Place your zImage containing the arc reactor kernel (or whatever kernel you're using) into the folder. You may need to rename it to boot.img-zImage Step 7: Go back one level to the android kitchen image folder, and click on the repackimg.bat file. This will rebuild your boot.img while incorporating the new zImage. Your boot image will be named image-new.img You can now fastboot flash this using the command Code (Text): fastboot flash boot image-new.img just like before!