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Irwin Strait-Line Red — Review & Specs | Pricepect | Pricepect

Home Measuring and Marking ToolsIrwin Strait-Line Red

Irwin Strait-Line Red — image 1

Irwin

Irwin Strait-Line Red

$9.14

65102Red1 Count (Pack of 1) Limited lifetime

Measuring and Marking Tools

Expert Review Analysis

The IRWIN STRAIT-LINE Marking Chalk Standard Red (Model 65102) is a weather-resistant, permanent red marking chalk formulated for reel-type chalk line boxes. It features a Hi-Flow Nozzle Cap to improve flow and reduce clumping, producing dark, sharp lines that remain visible for weeks despite jobsite wear and weather exposure.

✓ Best for: Professional contractors, framers, tilers, and decorators needing permanent, weather-resistant layout lines on rough surfaces like masonry or outdoors for framing, bricklaying, gutters, or drainpipes.✗ Not ideal for: Applications requiring temporary marks that need to be easily removed, as the chalk is designed for permanent staining.

Pros

✓Produces dark, sharp, permanent lines that remain visible for weeks
✓Hi-Flow Nozzle Cap reduces clumping and speeds up the filling process
✓Weather-resistant formulation withstands jobsite wear and exposure

Best Seller Rank History

Now#120Best#21Worst#126 -50

Lower = better sales rank

Rating Trend

Rating4.6/ 5Reviews446+-44 reviews

Specifications

General

BrandIrwin

ManufacturerIRWIN

Model65102

ColorRed

TypeMarking Chalk

Chemical Properties

pH (at 10% solids)8.5-9.5

Relative Density (H2O=1)3.40-3.45

Solubility in Water<0.0002 (trace)

Thermal Properties

Decomposition Temperature1,517 °F (825°C)

Safety

Eye Irritation RiskMild (Draize test: 750 ug/24H)

Dimensions & Weight

Height0.0 inches

Width0.0 inches

Depth0.0 inches

Weight1.0 Pounds

Research Sources

hardwickandsons.com

physics.purdue.edu

support.irwin.com

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User Reviews

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4.6

(446 reviews)

✓

Proprietary formulation optimized specifically for use with IRWIN chalk reels

✓Designed for heavy-duty professional use on rough surfaces like masonry

Cons

✗Permanent staining may be undesirable for temporary marking applications
✗Potential for mild eye irritation from components like calcium carbonate
✗No warranty coverage is provided for this product
✗Lacks specific bottle dimensions or height/width specifications in data
✗No data available on boiling point, flash point, or evaporation rate

How It Compares

vs. IRWIN Blue Standard Chalk

Advantages

✓Superior permanence with lines visible for weeks versus standard fading
✓Higher weather resistance for outdoor jobsite wear

Disadvantages

✗Permanent staining may be less versatile than standard temporary chalks
✗Specific density and pH data not provided for the blue variant for direct comparison

Choose IRWIN Red for permanent, weather-resistant outdoor layout lines, and IRWIN Blue for standard indoor or temporary marking needs.

vs. Generic Reel Chalk

Advantages

✓Hi-Flow cap reduces clumping compared to basic generic nozzles
✓Darker, sharper lines produced specifically with IRWIN reels

Disadvantages

✗Generic chalks often fade faster and lack weather resistance
✗Generic options do not offer the proprietary formulation optimized for IRWIN reels

Choose IRWIN Red for professional-grade durability and line quality, and generic chalks for cost-sensitive, short-term projects.