Sliding the A String Note While Playing the F# Riff

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While playing the open Low E note, use your ring (or pinky) finger to slide up the neck to the next power chord. At the end of the measure slide down from the 9th fret back to the 4th to repeat the riff:

    F#5         A5    B5
e|--------------------------
B|--------------------------
G|--------------------------
D|--------------------------
A|--4--4--4--/--7--/--9--\--
E|--2--2--2--0--5--0--7--0--