Skip to content
FREE SHIPPING ON ALL ORDERS $500 OR MORE
FREE SHIPPING ON ALL ORDERS $500 OR MORE
Carbothane 134 HG 2 part kit polyurethane gloss coating

Carbothane 134 HG by Carboline

by Carboline
$292.27 - $1,911.84
$292.27
$292.27 - $1,911.84
$292.27
Carbothane 134 HG is a high-performance, thin-film polyurethane coating designed for exceptional durability and aesthetics.
This product offers a high-gloss finish with superior weathering performance characteristics, making it suitable for various industrial and architectural applications.

Here are some key features:
  • Durability: Carbothane 134 HG provides a smooth, durable finish that excels in resistance against corrosion, abrasion, and chemical exposure. This makes it ideal for environments where longevity and protection are paramount.
  • Weatherability: This coating is known for its excellent weatherability. It far outperforms industry standards for color and gloss retention, adhering to or exceeding SSPC Level 3 urethane specifications.
  • Versatility: It is used extensively in virtually all industrial markets, including water and wastewater, oil and gas, petrochemical, offshore/marine, bridge and highway, architectural and commercial, power, pulp and paper, and mining.
  • Aesthetic Options: Available in many colors, including 1864 (White), S800 (White), 6666 (Safety Yellow), 1675 (Ignition Yellow), 5555 (Safety Red), C703
    (Grey), C705 (Light Grey), and C900 (Black). If a color you're interested in is not listed on this page, don't hesitate to get in touch with our support team.

Application: The product can be applied via spray for optimal coverage, with up to 25 oz/gal (20%) of thinner recommended, or by brush or roller for touch-ups and smaller areas. Mixing Part A and B according to manufacturer instructions is crucial to ensure the best results.

Theoretical Coverage: Coverage rates include
1123 ft²/gal at 1.0 mils, 
561 ft²/gal at 2.0 mils 
374 ft²/gal at 3.0 mils 
Allow for loss during mixing and application.

This coating enhances the appearance of the surface it's applied to and significantly extends the service life, making it a cost-effective solution for protective and decorative needs. For more detailed application guidance, please refer to the product's datasheet. 

CARBOTHANE 134 HG IS SOLD IN 1-GALLON & 5-GALLON KITS, INCLUDING PARTS A & B.

Product type: Aliphatic Acrylic Polyurethane
Finish: Carbothane has a gloss
Application Method: Conventional Spray, Airless Spray, Brush, or Roller
Mixing: 4:1 Ratio Parts A (Carbothane 134 HG) to B (Urethane Converter 811)
Thinner: Use Carboline Thinner 25, or 215

Contact our customer support today to discuss your project: 
(800) 567-5358

If you need a specific color not listed below, please indicate the exact color code desired in the order notes field during checkout. We can accommodate most requested colors. The color chart in the product images is for reference. 

Color: Black (C900)
Size: 1 Gallon
Coverage Calculator
⚠️ Carbothane 134 HG is a finish topcoat — it must be applied over a compatible primer or epoxy intermediate coat. It cannot be applied directly to bare steel. See the Coating Systems section below to choose the right system for your project.

Compatible Thinners

Thinner Application Max Rate
Thinner #25 › Spray (preferred) 20% (25 oz/gal)
Thinner #214 Spray 20% (25 oz/gal)
Thinner #72 Spray 20% (25 oz/gal)
Thinner #215 Brush & Roller only 20% (25 oz/gal)

Do not use Thinner #2 or #33 — those are for epoxy products. Use of unauthorized thinners voids warranty.

What Do I Need Under This?

New steel Carboguard 890 (4–6 mils) → Carbothane 134 HG
Steel over rust Carboguard 890 (6–8 mils over rust) → Carbothane 134 HG
High corrosion Carboguard 893 (primer) → Carboguard 890 → Carbothane 134 HG
Marine / offshore Carbozinc 11 (zinc primer) → Carboguard 890 → Carbothane 134 HG
Not sure? Call (800) 567-5358 — our coating specialists will recommend the right system for your environment.

Recommended Coating Systems

Two-Coat System — Standard Industrial
Intermediate / Primer Carboguard 890 4–6 mils DFT · self-priming
→
Topcoat ← You Are Here Carbothane 134 HG 2–3 mils DFT · UV-stable gloss
Zinc-Rich System — Marine / Offshore
Zinc Primer Carbozinc 11 galvanic protection
→
Intermediate Coat Carboguard 890 4–6 mils DFT · ties system together
→
Topcoat ← You Are Here Carbothane 134 HG 2–3 mils DFT

Frequently Purchased Together

Carboline Thinner No. 25 — for Carbothane 134 HG spray application
Carboline Thinner No. 25
Preferred spray thinner for 134 HG. Up to 20% addition rate.
$137.53 / gal
Shop Now
Carboguard 890 Self-Priming Epoxy — intermediate coat under Carbothane 134 HG
Carboguard 890 Epoxy
Most common intermediate coat under 134 HG. Self-priming, 4–6 mils.
$419.48 / 2-gal kit
Shop Now
Carboguard 893 Corrosion Resistant Epoxy Primer — for three-coat systems with Carbothane 134 HG
Carboguard 893 Primer
Corrosion-resistant primer for high-performance three-coat systems.
$439.48 / kit
Shop Now
Carbozinc 11 Inorganic Zinc Primer — for marine and offshore coating systems with Carbothane 134 HG
Carbozinc 11 Zinc Primer
Zinc-rich primer for marine and offshore systems. Maximum corrosion protection.
$292.27 / kit
Shop Now

Product Specs — Carbothane® 134 HG

Carbothane® 134 HG — Aliphatic Acrylic Polyurethane Topcoat by Carboline.
Thin-film, high-gloss finish with outstanding UV resistance, weatherability, and color/gloss retention. The preferred finish coat over epoxy systems for industrial and exterior applications.

✓ UV-Stable — Will Not Yellow or Chalk ✓ Indefinite Recoatability
✔ VOC compliant — current AIM regulations  •  ✔ USDA-inspected facility approved  •  ✔ Exceeds SSPC Paint 36 Level 3 urethane  •  ✔ AWWA D102 OCS 5 & 6  •  ✔ MIL-PRF-85285E Type II Class H

✏️ Need a project quote? Request Online

📞 Questions? Call (800) 567-5358 — Mon–Fri 8AM–5PM PST

Carbothane® 134 HG by Carboline

Carbothane 134 HG aliphatic acrylic polyurethane high-gloss topcoat by Carboline — industrial finish coat
Carbothane® 134 HG — High-Gloss UV-Stable Polyurethane Topcoat

Shipping Time

Call (800) 567-5358 for pricing and logistics questions.

Carboline orders ship from the regional warehouse nearest to your location.

Most orders ship within 2–3 business days of order placement. Sold in 1-gallon and 5-gallon kits including Parts A & B.

Shipping Map — Carboline Delivery Timing

Carboline US regional warehouse shipping map — 2, 3, and 4-day delivery transit zones
Typical transit times vary by destination zone.
Carbothane 134 HG polyurethane topcoat applied on industrial tank — high-gloss finish with superior UV and chemical resistance
Carbothane 134 HG applied as a finish coat on industrial steel.

Carbothane 134 HG Coverage Rates

Recommended DFT: 2–3 mils per coat. Thin film, high-coverage topcoat — a little goes a long way.

DFT per Coat Imperial Metric Typical Use
2.0 mils (50 microns) 561 ft²/gal 13.8 m²/l Standard finish coat
3.0 mils (75 microns) 374 ft²/gal 9.2 m²/l Heavy-duty or high-build finish
1.0 mil (25 microns) 1,123 ft²/gal 27.6 m²/l Theoretical reference (1 mil)

Allow for loss in mixing and application. Solids by volume: 70% ± 2%.
Source: Carboline Carbothane 134 HG TDS, January 2024

Mixing Instructions

Mix Ratio: 4:1 by volume (Part A to Part B)
Part A: Carbothane 134 HG  |  Part B: Urethane Converter 811

Power mix Part A separately. Add Part B and power mix together until uniform. DO NOT MIX PARTIAL KITS.

Pot life: 4 hours at 75°F (24°C) — shorter at higher temperatures.

⚠️ MOISTURE SENSITIVE: This product is moisture sensitive in the liquid stage and until fully cured. Protect from high humidity, rain, and dew until the coating is fully cured. Application above 80% relative humidity or exposure to moisture may result in loss of gloss or micro-bubbling.

Thinning by Application Method

All methods allow up to 25 oz/gal (20%) thinning — thinner selection varies by method:

Method Max Thinning Recommended Thinner
Spray (all types) Up to 20% (25 oz/gal) Thinner 214, Thinner 25, or Thinner 72
Brush Up to 20% (25 oz/gal) Thinner 215
Roller Up to 20% (25 oz/gal) Thinner 215

Low-HAP option: Carboline Thinner 236E may be used to minimize HAP and VOC emissions.

Use of unauthorized thinners may void the manufacturer's warranty.

Carbothane 134 HG high-gloss polyurethane topcoat application — spray applied over industrial epoxy primer system
Carbothane 134 HG applied by spray over epoxy. Mix ratio: 4:1 (A to B).

Application Conditions

Condition Material Temp. Surface Temp. Ambient Temp. Humidity
Minimum 50°F (10°C) 35°F (2°C) 35°F (2°C) 0%
Maximum 100°F (38°C) 120°F (49°C) 95°F (35°C) 80%
⚠️ Substrate temperature must be at least 5°F (3°C) above the dew point. Do not apply in fog, rain, or when surface condensation is present. If micro-bubbling occurs, allow a 30–60 minute induction time before continuing.

Curing Schedule

Surface Temp. Dry to Handle Dry to Recoat / Topcoat Final Cure
35°F (2°C) 36 hrs 36 hrs 14 days
50°F (10°C) 16 hrs 16 hrs 10 days
75°F (24°C) 8 hrs 8 hrs 7 days
90°F (32°C) 4 hrs 4 hrs 5 days

Based on 2.0 mil (50 micron) DFT. Higher film thickness or poor ventilation extend cure times.

Indefinite recoatability: There is no maximum recoat window. Before recoating aged Carbothane, wipe with Thinner 214 or 215 — a slight tack indicates the surface is ready without sanding. If no tack, lightly abrade before recoating.

Cold weather tip: Carboline Additive 101 can accelerate cure at low temperatures (as low as 20°F / -7°C) at 1–2 oz per mixed gallon. Note: Additive 101 reduces pot life by approximately 40–50%.

Compatible Substrates & Surface Preparation

Carbothane 134 HG is a finish/topcoat — it requires a compatible primer or epoxy intermediate coat. Do not apply directly to bare steel without an appropriate primer system.

Substrate Preparation Requirement
All Surfaces (General) Clean, dry, free of oil/grease/dust per SSPC-SP 1. Apply appropriate Carboline primer — consult your Carboline representative.
Galvanized Steel Prime with specific Carboline primer as recommended. Follow primer's product data sheet for prep requirements.
Previously Painted Lightly abrade to roughen and degloss. Existing coating must achieve minimum 3A rating per ASTM D3359 adhesion test. Clean per SSPC-SP 1.
Over Carboguard 890 Allow epoxy to cure to recoat window (8 hrs at 75°F). Surface must be clean and dry. Apply within 30-day maximum recoat window for best results.

Frequently Asked Questions — Carbothane 134 HG

What is the coverage rate for Carbothane 134 HG?
At the recommended 2–3 mil DFT: 561 ft²/gal at 2 mils and 374 ft²/gal at 3 mils (theoretical). As a thin-film topcoat, Carbothane goes significantly further per gallon than the epoxy coats beneath it.
Is Carbothane 134 HG UV resistant?
Yes — it's aliphatic, meaning it is inherently UV-stable. Unlike aromatic epoxies (such as Carboguard 890) which chalk and lose gloss outdoors, Carbothane retains its high-gloss finish and color in direct sunlight. It exceeds SSPC Paint 36 Level 3 urethane specifications.
What is the mix ratio and pot life?
Mix ratio is 4:1 by volume (4 parts Carbothane 134 HG Part A : 1 part Urethane Converter 811 Part B). Pot life is 4 hours at 75°F (24°C), shorter at higher temperatures. This product is moisture sensitive — avoid applying in high humidity or when moisture is present on the substrate.
Can it be recoated after years of exposure?
Yes — Carbothane 134 HG has indefinite recoatability. Before recoating aged Carbothane, wipe a test area with Thinner 214 or 215. If it shows a slight tack, the surface is ready for recoating without sanding. If no tack, lightly abrade the surface before applying the new coat.
What thinner should be used with Carbothane 134 HG?
For spray: Carboline Thinner 214, Thinner 25, or Thinner 72 — up to 25 oz/gal (20%). For brush and roller: Thinner 215 — up to 25 oz/gal. Do not use Thinner 2 (which is for epoxies like Carboguard 890).

Compare products

{"one"=>"Select 2 or 3 items to compare", "other"=>"{{ count }} of 3 items selected"}

Select first item to compare

Select second item to compare

Select third item to compare

Compare