The hub pilot wheels use one nut to hold both wheels on. Budd wheels have an outer nut to hold the outside wheel on and the inner stud nut to hold the inside nut on. The Budds also had right hand and left hand threads. The stud nuts will have an L stamped into the end.
Definition(s) Flammable Gas. Substance that exists exclusively in the gaseous state at normal atmospheric pressure and temperature and is capable of igniting and burning when mixed with air (oxygen) in the proper proportion and subjected to a source of ignition.
Flammable liquids are identified as liquids that have a flashpoint (minimum temperature needed for the liquid to produce a vapor with enough of a concentration to ignite) below 100 degrees Fahrenheit (F). There is an exception to this definition. If any of the components of the mixture have flashpoints of 100 deg. F or higher, then the material is classified as combustible rather than flammable. Another way to identify flammable liquids is by class. It is important to remember that with flammable liquids that it is the vapor coming off of the liquid that will ignite and burn, not necessarily the liquid itself.