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  1. Home
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  3. Slow Warning - W4-8
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Choose Your Reflectivity Grade

Compare visibility, durability, and ideal applications

Type I

Engineering Grade

Ideal Use

Parking lots

Brightness

Standard

General Lifespan

7 years

Night-time Visibility

500 feet away

Type IV

High Intensity Prismatic

Ideal Use

Roadways

Brightness

High

General Lifespan

10 years

Night-time Visibility

1000 feet away

Type IX

Diamond Grade

Ideal Use

High-speed roadways

Brightness

Maximum

General Lifespan

10+ years

Night-time Visibility

1500 feet away

Product Details

Slow Warning - W4-8

These durable Slow Warning signs are engineered to enhance road safety by alerting drivers to reduce speed in critical areas. Constructed from reflective aluminum with standard punched blanks, the W4-8 sign meets both DOT and MUTCD standards for maximum visibility and compliance. Designed with high intensity reflective materials, these signs provide clear communication to drivers in various lighting conditions. The W4-8 sign helps prevent accidents by creating awareness and encouraging drivers to slow down, ultimately protecting pedestrians, cyclists, and motorists in areas requiring reduced speed.

Spec • 2026
MUTCD Compliant

Sign Specifications

MUTCD Code

W4-8

Sign Type

Warning Sign

Shape

Diamond

Standard warning sign shape

Colors

ABC

Yellow background

Black legend

Compliance

MUTCD Compliant: This merge/lane transition warning sign meets federal standards per MUTCD Section 2C.38. Used to warn of lane changes ahead.

SizeDimensionsApplication
Conventional RoadDefault30×30"Two-lane roads, residential areas
Multi-Lane36×36"Multi-lane roads, higher speed limits
Expressway48×48"Expressways, freeways, high-speed roads
Compliance & Certifications

MUTCD Compliant

Federal standards

DOT Approved

State & Federal

ASTM D4956

Type III/IV/XI

10+ Years

Durability

Engineer Grade (EG)

Type: ASTM Type I

Lifespan: 5-7 years

Brightness: ~50 cd/lux/m²

Parking lots, low-speed areas, non-critical signage

Recommended

High Intensity Prismatic (HIP)

Type: ASTM Type III/IV

Lifespan: 10 years

Brightness: ~360 cd/lux/m²

Traffic signs, work zones, roadways

Diamond Grade (DG3)

Type: ASTM Type XI

Lifespan: 10-12 years

Brightness: ~580 cd/lux/m²

Critical signs, freeways, overhead signs

Install in advance of merge point or lane transition. Placement distance per MUTCD Table 2C-4.

MUTCD Reference: Section 2C.38

Reference: MUTCD Section 2C.38

Often Paired With

Signs commonly installed together per MUTCD guidelines

Right Turn Arrow Sign - W1-1R

W1-1R

Right Turn Arrow Sign

Road Work (distance) Sign - W20-1

W20-1

Road Work (distance) Sign

Pedestrian Crossing Sign - W11-2

W11-2

Pedestrian Crossing Sign

Road Closed (distance) Sign - W20-3

W20-3

Road Closed (distance) Sign

Stop Ahead (Symbol) Sign - W3-1

W3-1

Stop Ahead (Symbol) Sign

Workers Ahead Sign - W21-1

W21-1

Workers Ahead Sign

View All Warning Signs

Slow Warning - W4-8

Slow Warning  - W4-8
Min: 1 • Max: 1000
Unit Price:$0.00
Quantity:× 1
Total:$0.00

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