Combined Maximum and Minimum Speed Limits
- Category
- Regulatory
- Type
- Speed regulation
- Shape
- Rectangle
- Colors
- Black / White
- SHS release
- 3.0
- Federal status
- Current
What it means
Establishes the minimum lawful speed shown for traffic under normal conditions, subject to applicable law and conditions.
What the driver should do
Do not drive below the posted minimum unless conditions, traffic, or safety require a lower speed.
Typical placement / use
Used where a minimum speed regulation is established and posted.
50-State Standards Context
Federal sign R2-4a is part of the nationwide standardized study baseline. States may use the national MUTCD directly, supplement it, or use a state MUTCD. This does not mean every sign is installed everywhere, and state-specific codes, aliases, or variants are not inferred without independent verification.
State implementation model cross-checked in Gate 2 on June 4, 2026. Each state's official source controls any sign-specific code, alias, variant, or usage claim. Delaware was checked again on September 7, 2026 and its 2026 MUTCD remained marked pending approval.