Abstract: An apparatus and a method for purifying and heating air using photocatalytic oxidation. The apparatus includes a housing, a heater, and a photocatalytic oxidation unit disposed within the housing. The housing defines a flow path for air to move through the apparatus such that air from the environment is drawn into the apparatus and passes over the photocatalytic oxidation unit. A pollutant in the air from the environment adsorbs to a surface of the photocatalytic material coating the plates, and the surface of the photocatalytic material is exposed to ultraviolet light generated by the ultraviolet light source. The energy of the ultraviolet light activates the photocatalytic material, which then breaks down the pollutant leaving non-toxic components and purified air. The air then passes over the heater and back into the environment. A fan is also included to move air through the flow path.

Abstract: A safety lever pin for insertion into a safety lever pin receipt aperture of the sear assembly of an MK-19 grenade launcher such pin having a machined cylindrical body with an arm extending from the top thereof and structure to retain the safety lever pin within the safety lever pin receipt aperture to prevent its inadvertent falling out therefrom when the sear assembly is removed from the weapon and inverted.