You're missing parts of the designation, its E71T8-K6. This filler metal is a low alloy, self shielding flux cored filler metal for all position welding. The applicable AWS specification is A 5.29 "Specification for Low Alloy Steel Electrodes for Flux Cored Arc Welding". This specification contains all of the minimum requirements for this filler and is available from AWS.
The tradenames for this filler in the US are Hobart Fabshield 3Ni1 and Lincoln Electric Innershield NR-400 & NR - 207.
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