Nucamp T@B 320 Manual page 54

This is a "blow out" plug that fits into your city water Here is what you can use to put antifreeze into the city
connection, then connects to a standard air compressor water line; it has a hose connection on the tubing.
hose... KEEP THE PRESSURE WELL BELOW 50psi! Camco; costs around $25
To find this part search "Blow out plug" on Amazon. To find this part search this "Camco Mfg36003 RV
Hand Pump Kit" on Amazon
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