This is the Faber 232 bar, 9 litre Steel Cylinder with DIN/K valve and cylinder boot. For short and shallow dives, a 9l scuba tank can be sufficient. Some divers simply need very little air underwater and can be a bit more comfortable with a smaller cylinder. This includes especially kids.
To be able to nicely store your cylinder away, this tank comes with a flexible cylinder boot. This also protects the bottom of your cylinder and any surface it might come in contact with (e.g. a pool floor).
Faber makes their cylinders from high-quality 34CRMO4 Chromium Molybdenum Alloy Steel. They are constructed according to international standards. It comes with a DIN/K Valve included, which is exchangeable for any other threaded valve.