Default Firmware? Recovery?

Need some clarification about firmware and recovery file guys. I'm a bit confused because of the version number/s used to specify the recovery and firmware.

e.g. Flash_recovery_2.22.401.4

the main reason i'm asking this is because i converted my M8 to the GPe version (through RUU). I would now like to revert to the 'Sense base' but when it comes to flashing the firmware file the versions confuses me a bit, especially like the files i gave example of and the size of them. I grasp all the necessary on how to switch 'back to sense'.....its just how some sites/source label or quote the recovery and/or firmware files. Don't even want to mention RADIO

I don't think i need the RADIO tho, I know when a firmware is flashed all the needed files comes with it...Kernel, bootloader, radio etc.