This is a cable luber for forcing WD-40 type lubes thru the cable. We use these every day, and every self respecting do it yourselfer should have one in the toolbox.  13$ is the price, Cheap when you consider a cable is that much. 

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   Works on most types of control cables. Great for hard to access dashboard control cables in autos, too! Only one end needs to be disconnected in most cases.  home

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