4D laser level has self-leveling mode, manual mode and pulse mode. For the self-leveling mode, laser level will self-level within 3°, otherwise makes a beeping sound, Press and hold the brightness button for 2s to turn on the manual mode tilt mode, 4 x 360 laser level with 2 kinds of green lasers in weaker or stronger, switching to the weaker lasers, the indicator light will flash continuously.
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