... Flexible installed shut-off valve, easy to connect the pipe system.2. Suction strainer to filter the burr$dust out. It ... seal, more wearable, better heat resisting, avoid the leakage of lubrication oil.8. Heat treated shaft with high intension,more wearability, long ... ,more firmless.11.2L lubricated oil to keep best lubrication and compressor working well.12.Double oil sight glasses,easy to observe ...