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California road sign CW21-3 — Road machinery at specified distance ahead

MUTCD CW21-3 · Work zone signs

Road machinery at specified distance ahead

What it means

Warns of road machinery at specified distance ahead.

What to do about it

It is a work zone sign: orange means road work ahead. Slow down, leave extra space and expect sudden stops — fines are doubled in construction zones when workers are present. (MUTCD CW21-3.)

Practice this on the real test format

Signs are the part of the DMV written test people fail on, because reading them is a skill rather than a fact to memorize. Aprobify drills all 1034 of them, and tells you why each answer is what it is.

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Sign designations follow the MUTCD and the California MUTCD published by Caltrans; meanings are checked against the California Driver's Handbook (DL 600, rev. 6/2025). Edited by Fernando Aguilera. Aprobify is not affiliated with the California DMV.

Signs in the same family

These sit next to it in the work zone signs series — the ones most easily mixed up with it.

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