Which SR Blue or black Fuse


Which SR Blue fuse for ARC REF 5SE? It says 5A slo/blo 250V on the fuse but no size MM?any help? Anyone had any experience with either fuse and what was the result.
dskinner5
I thought my natural body oil WAS a contact enhancer, which has kept me from showering during Contact Cleaning Week. 
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So my SR Blue just arrived and I popped it into my amp's main IEC connector.  Straight out of the box it sounds a bit dark to me and the lows aren't quite as tight.  I will search the forum to see if others noticed this during the burn in period.  I know this fuse is directional so it's also possible I need to flip it around.  For the life of me I couldn't determine which way current flows through my connector (Note: I know current is supposed to flow from the S to the R printed on the fuse).  Any useful comments are welcome.
If you find the highs rolled off or recessed compared to how it used to sound, along with the lows being loose or phasey, just flip it and all should be good.

All the best,
Nonoise
You don’t have to know which way current or signal flows in the circuit since almost no aftermarket fuses are marked for directionality anyway. Thus, you should try both ways in any situation.