The numbers written on the "no U-turn" road marking indicate the hours during which U-turns are prohibited.

Explanation

Marking No. 1 prohibits U-turns, and the numbers show the time period of the prohibition. The letters and symbol are yellow.

Guides that explain this

• Japanese Signs That Mean the Opposite of What You Assume: Crosswind, End of Restriction, Minimum Speed
• Japanese Road Signs on the Written Test: The 5 Types Explained

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