Rip-stop nylon or dacron are the most common used fabrics. In stainless steel or aluminum tanks. These come in different sizes, the most popular of which hold 10 to 15 gallons. An altimeter to indicate altitude, a variometer to show whether it is going up or down, a compass to show directions, and a temperature gauge to tell how hot the air is at the top of the balloon. Each propane tank also has a fuel gauge.
Most balloonists carry a radio.
Some do not. A radio is required only in certain flying areas. Not usually, since most flights take place at low altitudes. However if a flight above 10,000 is planned, oxygen is taken along. A balloon Pilot Certificate is issued by the Federal Aviation Administration.