SessionOne is an indicator tool designed to visually mark specific trading sessions on a chart. It allows users to define custom time intervals, from any start time to any end time within a 24-hour period, to highlight the hours during which they prefer to trade. The tool supports renaming the session labels for clarity. SessionOne is applicable across various markets and symbols, including Forex pairs (EURUSD, GBPUSD, NZDUSD, USDJPY), cryptocurrencies (BTCUSD), commodities (XAUUSD), indices (NAS100), and stocks. This functionality aids traders in focusing on their preferred trading hours by clearly delineating session times on their charts.