A cart of liquid petroleum gas cylinders which are used for household cooking. To get a cylinder, one has to show address proof and pay about $75 which includes a two burner stove as well. Every twenty-one days, one is allowed to request a refill by going to the gas dealer from which they received the initial service. A fresh 15 kilogram cylinder costs $7 dollars and lasts up to three months depending on usage. It's amazing to me how hard the guys work who deliver the cylinders. They bike all day pulling these carts in rain or shine and carry them on their shoulders up several flights of stairs. Without these guys helping, I'm not sure how I would get a cylinder home! Here is an article on liquid petroleum gas.