Sharing a simple gap zone identifier, simply detects gap up/down areas and plots them for visual reference. Calculation uses new candle open compared to previous candle close and draws the zone, a mid point is plotted also as far too often it's significance is proven effective.
Works on any timeframe and market though I recommend utilizing timeframes such as weekly or daily for viewing at lower timeframes such as 5, 15 or 30 minutes.
Often price is observed reaching towards zone high/mid/low before rejection/bouncing. These gap zones can give quantitative basis for trade management.
Future features may include alerts based on price crossing up/down gap low, mid and highs. Feel free to message with any other suggestions.