A version of Atari DOS 2.5 to be used with Turbo Basic. When using a standard version of DOS 2.5, you can't easily switch from DOS 2.5 back to Turbo Basic. This modified version of DOS 2.5 will let you do that by pressing the 'B' key. The standard version of DOS 2.5 uses the 'B' key to switch back to Atari BASIC, so no functionality is lost by overriding the 'B' key.
Here are two versions of DOS 2.5 TB for download. The first is a zipped DCM file, unzip it and then use Disk Communicator to extract it. The second is a zipped ATR file, for those wanting to use it on an emulator.