These are levels based on volume. The idea is that candles of high volume a higher amount of traders with active long/short positions to either close out, protect, or add to.
A stack of red candles means that area is a point of interest, similar to a VPVR POC.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in publication is governed by House rules. You can favorite it to use it on a chart.
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