Did you know you're typical "butane refill" isn't just butane. Its a mixture or blend of flammable hydrocarbons, mostly n-butane, iso-butane, and n-propane. At Capital Butane, our standards for exceeding quality and expectations were most important when creating the first specially formulated LPG mixture. Maintaining those standards, N-Blend was mixed here in the United States using only the highest quality N-BUTANE and N-PROPANE, for consumers who prefer maximum pressure. N-Propane has specific properties that raise the pressure of the cans contents and provide maximum burning temperatures, especially at higher elevations and colder climates. FREE SHIPPING ON ALL PRODUCTS!