Valve

• The valve is a traditional "on and "off" K-valve. The valve is opened by turning the valve handle counter-clockwise, and closed by turning it in the opposite direction.
  
  

Cylinder Material

• Scuba cylinders are traditionally made from steel or aluminum. Aluminum tanks are favored more worldwide as they are cheaper and more lightweight than steel tanks, although traditionally do not last as long.
  
  

Cylinder Markings

• The markings stamped on the neck of the cylinder are the date of the last hydrostatic test, metal type and manufacturer. Stickers attached to the tank show dates of visual inspections and the gas type contained in the cylinder.
  
  

Valve Regulator Attachment

• The two main types of valve attachment on a scuba tank are the international yoke valve or a DIN valve. The yoke valve is a valve fitted with an O-ring, which a regulator is placed over to attach. A DIN valve is a threaded valve into which a regulator screws.
  
  

Tank Boot

• A tank boot is placed over the base of the tank to prevent damage to the tank and the surrounding environment when the tank is put down.