Castro ROAST 100 PS| PORTABLE AIR COMPRESSOR Thank you for purchasing the 100 PSI Portable Air Compressor from Astral. This is a programmable Air Compressor with digital display that cane used to monitor air pressure while inflating. Once the per-set pressure is reached, the Air Compressor will automatically shut off. For optimal performance and safety, please read and follow all of the instructions below before operating the device, Please keep this manual for future reference.