Half and full facepiece parts and accessories help maintain optimal respirator performance. Inhalation and exhalation valves facilitate safe breathing. Bayonet, lens frame and speaking diaphragm assemblies contain multiple parts for simple replacement. Spectacle kits allow workers to wear corrective lenses. Other full facepiece parts include replacement lenses, lens clamps, frames and retainers. Nose cups, valve assemblies and nose cup valve disks are available to replace individual components in existing respirators.