Butane extraction, or BHO, is a method of extraction that uses the chemical solvent, butane, to pass over the botanical plants and plant materials. The butane is then separated from the mixture using heat and sometimes a vacuum pump or vacuum oven. The finished product, at room temperature, is typically a golden, soft wax. When heated, it is melted into a clear to yellowish amber oil. At its very purest, the substance resembles a thin, hard glass. The substance, usually golden amber, hardens into a thin layer that can be broken down by heat, resulting in butane hash oil.
The end products have been branded as BHO, Butane Hash Oil, Earwax, Honey Oil and Shatter. These products are all comparable, and mainly differ in appearance due to the various melting and extraction points.”