RE43E Foam
RE43E is a medium, closed-cell EPDM and Neoprene blend foam with a compression deflection of 9–13 psi at 25% per ASTM D1056 and a density of 7–11 lb/ft³, available in four thicknesses from 1/16″ to 1/4″. The material has a service temperature range of -70°F to 220°F, passes FMVSS-302 at .098″ or thicker, and is classified ASTM D1056-07 2A3 and ASTM D6576-07 Type II A, B Medium. It carries MIL-R-6130C II-A Medium and MIL-C-3133C MIL STD 670B (RE11) designations.
Key Properties
- Compression Deflection @ 25%: 9–13 psi (ASTM D1056)
- Tensile Strength: 100 psi (ASTM D412)
- Elongation: 125% (ASTM D412)
- Compression Set (Max): 30% (ASTM D1056)
- Density: 7–11 lb/ft³ (ASTM D1056)
- Service Temperature: -70°F to 220°F
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- Specifications
- Applications
- General Info
- FAQs
Physical Properties
| Property | Value | Test Method |
| Thickness | 1/16″, 1/8″, 3/16″, 1/4″ | — |
| Color | Black | — |
| Polymer | Ethylene Propylene Diene Monomer (EPDM) | — |
| Density | 7–11 lb/ft³ | ASTM D1056 |
| Thermal Conductivity | .380 btu/(h·ft²·°F) | — |
Mechanical Properties
| Property | Value | Test Method |
| Compression Deflection @ 25% | 9–13 psi | ASTM D1056 |
| Compression Set (Max) | 30% | ASTM D1056 |
| Water Absorption (Max) | 5% | ASTM D1056 |
| Compression Deflection Change After Oven Aging (Max) | ±30% | ASTM D1056 |
| Tensile Strength | 100 psi | ASTM D412 |
| Elongation | 125% | ASTM D412 |
| Tear Strength | 15 lb/in | ASTM D624 |
| Resilience | 20% | ASTM D2632 |
Thermal Properties
| Property | Value | Test Method |
| Service Temperature | -70°F to 220°F | — |
| High Intermittent Temperature | 250°F | — |
Flame & Fire Performance
| Property | Value | Test Method |
| Flame Retardant | Yes | — |
| FMVSS-302 | Pass .098″ or thicker | — |
Regulatory / Compliance Data
| Property | Value | Test Method |
| ASTM D1056-07 | 2A3 | — |
| ASTM D1056-78 | RE43 | — |
| ASTM D1056 Suffix’s | A1, C1, F2, M | — |
| ASTM D6576-07 | Type II A, B Medium | — |
| MIL-R-6130C | II-A Medium | — |
| MIL-C-3133C MIL STD 670B | RE11 | — |
Compliance
- FMVSS-302 — Compliant (Pass, .098″ or thicker)
- MIL-R-6130C — II-A Medium
- MIL-C-3133C MIL STD 670B — RE11
- NEMA enclosure seals requiring medium deflection resistance, MIL-R-6130C II-A Medium compliance, and the widest service temperature range in the RE series (-70°F to 220°F)
- HVAC exterior curb seals where medium compression resistance provides a more robust gasket under higher closure forces than soft/medium grades
- Appliance gaskets and seals requiring medium EPDM foam with improved compression set (max 30%) and reduced water absorption (max 5%) versus softer grades
- Military and defense applications requiring MIL-R-6130C II-A Medium and MIL-C-3133C MIL STD 670B (RE11) compliance in a medium closed-cell EPDM foam
- General environmental sealing applications requiring ASTM D1056 2A3 / ASTM D6576-07 Type II Medium classification where higher tear strength (15 lb/in) over soft/medium grades is required
Common industries: HVAC, appliance, construction, automotive, military, industrial manufacturing.
RE43E is the medium-grade closed-cell EPDM and Neoprene blend foam in the RE series, classified ASTM D1056-07 2A3 and ASTM D6576-07 Type II A, B Medium. It is designed for NEMA enclosure seals, HVAC exterior curb seals, and appliance gaskets and seals where more compression resistance than the soft/medium RE42E grade provides is needed.
Available in four thicknesses from 1/16″ to 1/4″, it delivers medium firmness with high and low temperature resistance and flame retardant performance. The TDS specifically highlights higher tensile strength as a product feature for this grade.
RE43E has the widest service temperature range in the RE series at -70°F to 220°F — both the coldest low-temperature rating and the highest continuous service temperature in the series. The material passes FMVSS-302 at .098″ or thicker. MIL-R-6130C classification is II-A Medium; MIL-C-3133C MIL STD 670B designation is RE11. Resilience is 20% per ASTM D2632. Compression set (max) is 30% per ASTM D1056 — the lowest in the RE series alongside RE45E.
Water absorption (max) is 5% per ASTM D1056 — lower than RE41E and RE42E. Tensile strength is 100 psi and elongation is 125% per ASTM D412. Tear strength is 15 lb/in per ASTM D624. Compression deflection change after oven aging (max) is ±30% per ASTM D1056. Thermal conductivity is .380 btu/(h·ft²·°F). High intermittent temperature is 250°F. ASTM D1056-78 designation: RE43. ASTM D1056 Suffix’s: A1, C1, F2, M. No UL listings are present on this TDS.
Compliant with FMVSS-302 (Pass, .098″ or thicker), MIL-R-6130C II-A Medium, and MIL-C-3133C MIL STD 670B (RE11).
What differentiates RE43E from other grades in the RE EPDM foam series?
RE43E is the medium grade in the RE series at 9–13 psi compression deflection at 25% and 7–11 lb/ft³ density. It has the widest service temperature range in the series at -70°F to 220°F — both colder and hotter than RE41E and RE42E (-40°F to 200°F). Its compression set (max) of 30% ties RE45E for the lowest in the series, and its water absorption (max) of 5% is lower than the 10% for the two softer grades.
Tear strength of 15 lb/in is higher than RE41E's and RE42E's 9.6 lb/in. The TDS specifically describes "higher tensile strength" as a product feature distinguishing this grade. No UL listings are present on this TDS.
Why is compression set critical for a medium closed-cell EPDM foam used in NEMA enclosure and HVAC sealing?
In NEMA enclosure and HVAC exterior curb sealing applications, the foam gasket must maintain consistent contact force against the mating surface across thermal cycling, sustained closure loads, and exposure to outdoor environmental conditions. A medium foam that permanently deforms under its installed load loses the compression resistance advantage that distinguishes it from the softer grades, reducing seal contact force to below design values and allowing moisture, dust, and air infiltration.
RE43E's compression set (max) of 30% per ASTM D1056 — the lowest in the series for this density class — confirms better dimensional recovery than softer grades under comparable service conditions.
What is the service temperature range for RE43E?
The service temperature range is -70°F to 220°F as listed on the TDS — the widest in the RE series. High intermittent temperature is 250°F.
Is RE43E suitable for regulated automotive and military environments?
Yes. RE43E passes FMVSS-302 at .098" or thicker, meets MIL-R-6130C II-A Medium, and meets MIL-C-3133C MIL STD 670B (RE11), as listed on the TDS. No UL listings are present on this TDS.
How should RE43E be specified?
Specify grade (RE43EPDM), ASTM D1056 designation (2A3), applicable suffix designations (A1, C1, F2, M), thickness (1/16", 1/8", 3/16", or 1/4"), color (Black), applicable compliance requirements (FMVSS-302, MIL-R-6130C II-A Medium, MIL-C-3133C MIL STD 670B RE11), dimensional tolerances, and finished format (sheet, slit roll, or die-cut component).
