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.
Part #: 2203 0387 00
Part #: 2204135111
Part #: 1630144405
Part #: 1089949693
Part #: 1089951334