This is TRSI and Pivothigh and Pivotlow combined indicator.
TRSI itself generates signals when crossing 30/70 or 20/80 levels (as per your choice) to buy or to sell accordingly.
These crossing levels are marked on the chart with triangles and their direction.
The channel you see on the chart is based on high and low pivots, by defauld 4 bars left and 2 bars...