A hook/dipper is a tool used to keep a wick straight. Sometimes, when a candle burns for hours, especially if you forgot to trim it before lighting, the wick leans or curls. If you don’t center and straighten the wick, it will lead to uneven burn the next time. After using a candle snuffer to extinguish the candle flame, use the hook to lift and straighten the wick. Recenter the wick as needed.