How does one tell if a wire requires the use of gas or is for no gas? thanks
If it's new wire it should say in the literature or label. Generally anything described as flux cored wire is for use without gas.
That wire you found was described as cored not flux cored, and would need to be used with gas.
You can usually tell just by looking at it. Standard wire used with a shielding gas is normally copper coated & Flux-Cored, gas less has a dull grey appearance.
Bear in mind that you can't just stick gas-less wire on any machine, it runs on a different polarity to standard wire & the machine must have the facilty to change this (two sockets for the earth lead marked - & +).
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