This SDX12 kit comes with a sealed, 1.0 cubic foot cabinet. In this configuration, the SDX12 has an f3 of about 40 Hz with a smooth sealed box rolloff. If you have an amplifier with boost, you can add 6 dB of boost with a Q of 1 centered at 25 Hz and you will end up with about a 23 Hz f3.
The flatpack comes fully rabbeted and dadoed for easy assembly with well braced 0.75" walls and a 1.5" front baffle. 14" x 14" x 14" external dimensions.