the AVAP Band displays:
1. The AVWAP using High as the source
2. The AVWAP using OHLC4 as the source
3. The AVWAP using Low as the source
This is just a different way of visualising VWAP from an anchored point in time (Band vs Line)
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 a publication is governed by House Rules. You can favorite it to use it on a chart.