What is this component?

This is from an AKAI AM-U22 amplifier. There are quite a few of these items (circled in red) on the board and the circuit diagram shows them as a jumper link. Note that the one circled is splitting.
Is this a jumper or something else?

If this is some type of jumper what is the go with this design?
 

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Thanks for the replies.
I didn't know about 0 ohm resistors until your replies. Have done some research and understand their use now.
All my tools are at another place 100 kilometres away and won't be going there for a couple of weeks so I am unable to test the bad resistor at present. Would it be reasonable any to say that the bad resistor could read any value?