RE42E Foam
RE42E is a soft/medium, closed-cell EPDM and Neoprene blend foam with a compression deflection of 5–9 psi at 25% per ASTM D1056 and a density of 4–8 lb/ft³, available in four thicknesses from 1/16″ to 1/4″. The material has a service temperature range of -40°F to 200°F, passes FMVSS-302 at .098″ or thicker, and is classified ASTM D1056-07 2A2 and ASTM D6576-07 Type II A, B, C Soft/Medium. It carries MIL-R-6130C II-A Soft/Medium and MIL-C-3133C MIL STD 670B (RE7) designations.
Key Properties
- Compression Deflection @ 25%: 5–9 psi (ASTM D1056)
- Tensile Strength: 100 psi (ASTM D412)
- Elongation: 125% (ASTM D412)
- Compression Set (Max): 35% (ASTM D1056)
- Density: 4–8 lb/ft³ (ASTM D1056)
- Service Temperature: -40°F to 200°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 | 4–8 lb/ft³ | ASTM D1056 |
| Thermal Conductivity | .300 btu/(h·ft²·°F) | — |
Mechanical Properties
| Property | Value | Test Method |
| Compression Deflection @ 25% | 5–9 psi | ASTM D1056 |
| Compression Set (Max) | 35% | ASTM D1056 |
| Water Absorption (Max) | 10% | ASTM D1056 |
| Compression Deflection Change After Oven Aging (Max) | ±30% | ASTM D1056 |
| Tensile Strength | 100 psi | ASTM D412 |
| Elongation | 125% | ASTM D412 |
| Tear Strength | 9.6 lb/in | ASTM D624 |
| Resilience | 35% | ASTM D2632 |
Thermal Properties
| Property | Value | Test Method |
| Service Temperature | -40°F to 200°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 | 2A2 | — |
| ASTM D1056-78 | RE42 | — |
| ASTM D1056 Suffix’s | A1, C1, F2, M | — |
| ASTM D6576-07 | Type II A, B, C Soft/Medium | — |
| MIL-R-6130C | II-A Soft/Medium | — |
| MIL-C-3133C MIL STD 670B | RE7 | — |
Compliance
- FMVSS-302 — Compliant (Pass, .098″ or thicker)
- MIL-R-6130C — II-A Soft/Medium
- MIL-C-3133C MIL STD 670B — RE7
- Garage door and tonneau cover seals where slightly greater deflection resistance than RE41E is needed for more positive seal contact under variable closure loads
- HVAC and duct seals requiring a soft/medium EPDM foam with MIL-R-6130C II-A Soft/Medium military compliance
- Exterior mailbox and enclosure seals requiring FMVSS-302 flame compliance in a soft/medium closed-cell EPDM format
- Military and defense applications requiring MIL-R-6130C II-A Soft/Medium and MIL-C-3133C MIL STD 670B (RE7) compliance in a thin-gauge EPDM foam
- General soft/medium environmental sealing applications requiring ASTM D1056 2A2 / ASTM D6576-07 Type II Soft/Medium classification at thicknesses from 1/16″ to 1/4″
Common industries: Automotive, HVAC, construction, military, general manufacturing.
RE42E is the soft/medium-grade closed-cell EPDM and Neoprene blend foam in the RE series, classified ASTM D1056-07 2A2 and ASTM D6576-07 Type II A, B, C Soft/Medium. It is designed for garage door seals, tonneau cover seals, HVAC/duct seals, and exterior mailbox box seals where a slightly firmer foam than the soft RE41E grade is needed. Available in four thicknesses from 1/16″ to 1/4″, it provides soft/medium deflection resistance with high and low temperature resistance and flame retardant performance across a service range of -40°F to 200°F.
The material passes FMVSS-302 at .098″ or thicker and is flame retardant (Yes). MIL-R-6130C classification is II-A Soft/Medium; MIL-C-3133C MIL STD 670B designation is RE7. Resilience is 35% per ASTM D2632. Compression set (max) is 35% per ASTM D1056 — lower than RE41E’s 40%. Water absorption (max) is 10% per ASTM D1056. Tensile strength is 100 psi and elongation is 125% per ASTM D412. Tear strength is 9.6 lb/in per ASTM D624.
Compression deflection change after oven aging (max) is ±30% per ASTM D1056. Thermal conductivity is .300 btu/(h·ft²·°F). High intermittent temperature is 250°F. ASTM D1056 designations: ASTM D1056-78 RE42. 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 Soft/Medium, and MIL-C-3133C MIL STD 670B (RE7).
What differentiates RE42E from other grades in the RE EPDM foam series?
RE42E is the soft/medium grade in the RE series at 5–9 psi compression deflection at 25%, positioned between the soft RE41E (2–5 psi) and the medium RE43E (9–13 psi), sharing the same 4–8 lb/ft³ density range as RE41E. It introduces MIL-R-6130C II-A Soft/Medium and MIL-C-3133C MIL STD 670B (RE7) designations not present on RE41E. Compression set (max) improves to 35% versus RE41E's 40%. Thermal conductivity is .300 btu/(h·ft²·°F) — the lowest in the RE series. No UL listings are present on this TDS.
Why is compression set critical for a soft/medium closed-cell EPDM foam used in sealing applications?
In garage door, tonneau cover, and HVAC duct sealing applications, the foam must maintain consistent contact force against the mating surface across repeated compression cycles and long service intervals. A soft/medium grade that takes a high compression set will gradually flatten under repeated cycling — losing the slight additional contact pressure that distinguishes it from the softer grade, and reducing sealing effectiveness over time. RE42E's compression set (max) of 35% per ASTM D1056 is lower than RE41E's 40%, making it the better choice where improved long-term seal retention at soft/medium deflection resistance is required.
What is the service temperature range for RE42E?
The service temperature range is -40°F to 200°F as listed on the TDS. High intermittent temperature is 250°F.
Is RE42E suitable for regulated automotive and military environments?
Yes. RE42E passes FMVSS-302 at .098" or thicker, meets MIL-R-6130C II-A Soft/Medium, and meets MIL-C-3133C MIL STD 670B (RE7), as listed on the TDS. No UL listings are present on this TDS.
How should RE42E be specified?
Specify grade (RE42EPDM), ASTM D1056 designation (2A2), 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 Soft/Medium, MIL-C-3133C MIL STD 670B RE7), dimensional tolerances, and finished format (sheet, slit roll, or die-cut component).
