The 1089948298 contact block is sits on the backside of the emergency stop button. This sends a signal to shut down the compressor when the emergency stop button is pushed. This contact block was used on a wide variety of Chicago Pneumatic and Atlas Copco air compressors.
The part number may be displayed in your manual as 1089948298, 1089-9482-98 or 1089 9482 98.
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