This Aerospace Standard (AS) defines the requirements for a heavy braid polytetrafluoroethylene (PTFE) lined, metallic reinforced, hose assembly suitable for use in high temperature, 400 \mDF, high pressure, 3000 psi, aircraft hydraulic fluid systems, also for use in pneumatic systems which allow some gaseous diffusion through the PTFE wall. The -20 size operating temperature is limited to 275 \mDF maximum.