Underground Shielded Couplings
Built for demanding underground pipe transitions where resistance to heavy earth loads, shear forces and pipe misalignment matters.
Built for Tough Underground Connections
Strong Back RC Couplings combine Fernco flexible sealing performance with stainless steel reinforcement for a stronger underground transition.
Extra Strength
Designed to resist heavy earth loads and shear forces in demanding underground applications.
Shielded Support
Features a .012" stainless steel shear ring and molded-in bushing for added stability.
Broad Range
Available for clay, cast iron, plastic, concrete, ductile iron and other underground piping systems.
Best For
Built for Underground Transitions
Strong Back RC Couplings are designed for pipe transitions where the outside diameters, pipe materials or jobsite conditions require added alignment support. The molded-in bushing works with the stainless steel shear ring to help keep the connection stable while the flexible elastomeric sleeve maintains a dependable seal.
Specifications
Coupling
- Standards: Manufactured to conform to ASTM C1173 and CSA B602 performance requirements
- Installation Torque: 60 in-lbs.
- Maximum Test Pressure: 4.3 PSI / 29.6 KPA
- Maximum Operating Temperature: 140°F non-consistent
Gasket
- Standards: Manufactured to meet material requirements of CSA B602, ASTM D5926 and ASTM C1173
- Hardness: Shore “A” 65 ±5
- Tensile Strength: 1000 psi minimum
- Elongation: 250% minimum
- Brittleness: -40°F
Clamp
- Clamp Housing: 301 stainless steel
- Clamp Band: 301 stainless steel
- Clamp Screw: 305 stainless steel
Shear Ring
- Material: 300 series stainless steel
- Thickness: .012"
- Widths: 1.50", 2.13", or 4"
- AIS/BABA: 15" and below are compliant
AIS & BABA Compliant Options
Strong Back RC Couplings 15" and below are Made in the USA and AIS/BABA compliant, supporting federally funded underground infrastructure projects where domestic sourcing matters.
AIS/BABA
Compliant
Strong Back RC Part Numbers
Search by part number, series, pipe transition or outside diameter.
1001 Series - Clay to Clay
| Part No. | Side A (in) | Side A (mm) | Side B (in) | Side B (mm) | Width C (in) | Width C (mm) |
|---|---|---|---|---|---|---|
| 1001-44RC | 5.29 | 134.37 | 5.29 | 134.37 | 4.10 | 104.14 |
| 1001-44WCRC | 5.51 | 139.95 | 5.51 | 139.95 | 3.97 | 100.84 |
| 1001-64RC* | 7.50 | 190.5 | 5.50 | 139.70 | 6.02 | 152.91 |
| 1001-66RC | 7.50 | 190.5 | 7.50 | 190.50 | 6.02 | 152.91 |
| 1001-66WCRC | 7.87 | 199.90 | 7.87 | 199.90 | 5.925 | 150.50 |
| 1001-88RC | 9.65 | 245.11 | 9.65 | 245.11 | 5.99 | 152.15 |
| 1001-88WCRC | 10 | 254.00 | 10 | 254.00 | 5.945 | 151.00 |
| 1001-1010RC | 12.40 | 314.96 | 12.40 | 314.96 | 5.90 | 149.86 |
| 1001-1010WCRC | 12.40 | 314.96 | 12.40 | 314.96 | 5.90 | 149.86 |
| 1001-1212RC | 14.51 | 368.55 | 14.51 | 368.55 | 6.38 | 162.05 |
| 1001-1212WCRC | 15.25 | 387.35 | 15.25 | 387.35 | 6.42 | 163.07 |
| 1001-1515RC | 18.14 | 460.76 | 18.14 | 460.76 | 9.89 | 251.21 |
| 1001-1818RC | 21.90 | 556.26 | 21.90 | 556.26 | 9.63 | 244.60 |
| 1001-2424RC | 28.97 | 735.84 | 28.97 | 735.84 | 9.89 | 251.21 |
* Supplied with reducer.
Maximum Test Pressure: 4.3 PSI (29.6 KPA)
Maximum Operating Temperature: 140° F non-consistent
1002 Series - Clay to Cast Iron or Plastic
| Part No. | Side A (in) | Side A (mm) | Side B (in) | Side B (mm) | Width C (in) | Width C (mm) |
|---|---|---|---|---|---|---|
| 1002-43RC* | 5.29 | 134.37 | 3.38 | 85.85 | 4.10 | 104.14 |
| 1002-44RC | 5.36 | 136.14 | 4.51 | 114.55 | 4.07 | 103.38 |
| 1002-44WCRC | 5.44 | 138.18 | 4.55 | 115.57 | 3.96 | 100.58 |
| 1002-46RC* | 6.60 | 167.64 | 5.13 | 130.18 | 5.74 | 145.80 |
| 1002-55RC* | 6.60 | 167.64 | 5.50 | 139.70 | 5.74 | 145.80 |
| 1002-64RC* | 7.50 | 190.5 | 4.50 | 114.30 | 6.02 | 152.91 |
| 1002-64WCRC | 7.84 | 199.14 | 4.5 | 114.30 | 5.955 | 151.26 |
| 1002-64WCRC-SDR | 7.84 | 199.14 | 4.38 | 111.25 | 5.955 | 151.26 |
| 1002-66RC | 7.50 | 190.5 | 6.56 | 166.65 | 5.89 | 149.68 |
| 1002-66WCRC | 7.84 | 199.14 | 6.52 | 165.61 | 5.955 | 151.26 |
| 1002-86RC* | 9.65 | 245.11 | 6.63 | 168.40 | 5.99 | 152.15 |
| 1002-88RC | 9.76 | 247.95 | 8.57 | 217.63 | 5.96 | 151.38 |
| 1002-88WCRC | 10 | 254.00 | 8.49 | 215.65 | 5.92 | 150.37 |
| 1002-10-8RC* | 12.40 | 314.96 | 8.50 | 215.90 | 5.90 | 149.86 |
| 1002-1010RC* | 12.40 | 314.96 | 10.75 | 273.05 | 5.90 | 149.86 |
| 1002-1010WCRC | 12.40 | 314.96 | 10.75 | 273.05 | 5.90 | 149.86 |
| 1002-1210RC* | 14.51 | 368.55 | 12.60 | 320.04 | 6.38 | 162.05 |
| 1002-1212RC* | 14.51 | 368.55 | 12.60 | 320.04 | 6.38 | 162.05 |
| 1002-1212WCRC | 15.25 | 387.35 | 12.6 | 320.04 | 6.42 | 163.07 |
| 1002-1215RC* | 15.25 | 387.35 | 14.38 | 365.25 | 6.42 | 163.07 |
| 1002-1515RC* | 18.14 | 461.76 | 15.40 | 391.16 | 9.89 | 251.27 |
| 1002-1818RC* | 21.90 | 556.26 | 19.00 | 482.60 | 9.63 | 244.60 |
| 1002-2121RC* | 25.46 | 646.68 | 22.30 | 566.42 | 9.89 | 251.21 |
| 1002-2424RC* | 28.97 | 735.84 | 25.00 | 635.00 | 9.89 | 251.21 |
* Supplied with reducer.
Maximum Test Pressure: 4.3 PSI (29.6 KPA)
Maximum Operating Temperature: 140° F non-consistent
1003 Series - Clay to Ductile Iron
| Part No. | Side A (in) | Side A (mm) | Side B (in) | Side B (mm) | Width C (in) | Width C (mm) |
|---|---|---|---|---|---|---|
| 1003-44RC | 5.41 | 137.41 | 4.94 | 125.48 | 4.07 | 103.38 |
| 1003-66RC | 7.25 | 184.15 | 6.84 | 173.74 | 5.93 | 150.62 |
| 1003-66WCRC | 8.00 | 203.20 | 6.90 | 175.26 | 6.00 | 152.40 |
| 1003-68RC* | 9.05 | 229.87 | 7.20 | 182.88 | 5.98 | 151.89 |
| 1003-8-10RC* | 11.22 | 284.99 | 9.65 | 245.11 | 5.97 | 151.51 |
| 1003-88RC | 9.75 | 247.65 | 9.06 | 230.12 | 5.94 | 150.88 |
| 1003-1010RC* | 12.40 | 314.96 | 11.12 | 282.45 | 5.90 | 149.86 |
| 1003-1212RC* | 14.51 | 368.55 | 13.20 | 335.28 | 6.38 | 162.05 |
| 1003-1818RC* | 21.90 | 556.26 | 19.50 | 495.30 | 9.63 | 244.63 |
* Supplied with reducer.
Maximum Test Pressure: 4.3 PSI (29.6 KPA)
Maximum Operating Temperature: 140° F non-consistent
1004 Series - Concrete to Concrete
| Part No. | Side A (in) | Side A (mm) | Side B (in) | Side B (mm) | Width C (in) | Width C (mm) |
|---|---|---|---|---|---|---|
| 1004-44RC | 5.51 | 139.95 | 5.51 | 139.95 | 3.97 | 100.84 |
| 1004-66RC | 7.58 | 192.53 | 7.58 | 192.53 | 5.94 | 150.88 |
| 1004-88RC | 10.38 | 263.65 | 10.38 | 263.65 | 5.90 | 149.86 |
| 1004-1010RC | 12.40 | 314.96 | 12.40 | 314.96 | 5.90 | 149.86 |
| 1004-1212RC | 15.25 | 387.35 | 15.25 | 387.35 | 6.42 | 163.07 |
| 1004-1515RC | 19.74 | 501.40 | 19.74 | 501.40 | 9.89 | 251.21 |
* Supplied with reducer.
Maximum Test Pressure: 4.3 PSI (29.6 KPA)
Maximum Operating Temperature: 140° F non-consistent
1006 Series - Concrete to Cast Iron or Plastic
| Part No. | Side A (in) | Side A (mm) | Side B (in) | Side B (mm) | Width C (in) | Width C (mm) |
|---|---|---|---|---|---|---|
| 1006-44RC* | 5.51 | 139.95 | 4.50 | 114.3 | 3.97 | 100.84 |
| 1006-64RC* | 7.58 | 192.53 | 4.38 | 111.25 | 5.94 | 150.88 |
| 1006-66RC* | 7.58 | 192.53 | 6.63 | 168.28 | 5.94 | 150.88 |
| 1006-86RC* | 10.38 | 263.65 | 6.38 | 162.05 | 5.90 | 149.86 |
| 1006-88RC* | 10.38 | 263.65 | 8.50 | 215.90 | 5.90 | 149.86 |
| 1006-10-8RC* | 12.4 | 314.96 | 8.38 | 212.85 | 5.9 | 149.86 |
| 1006-1010RC* | 12.40 | 314.96 | 10.75 | 273.05 | 5.90 | 149.86 |
| 1006-1210RC* | 15.25 | 387.35 | 10.6 | 269.24 | 6.42 | 163.07 |
| 1006-1212RC* | 15.25 | 387.35 | 12.60 | 320.04 | 6.42 | 163.07 |
| 1006-1515RC* | 19.74 | 501.40 | 15.40 | 391.16 | 9.89 | 251.28 |
* Supplied with reducer.
Maximum Test Pressure: 4.3 PSI (29.6 KPA)
Maximum Operating Temperature: 140° F non-consistent
1051 Series - Ductile Iron to Cast Iron or Plastic
| Part No. | Side A (in) | Side A (mm) | Side B (in) | Side B (mm) | Width C (in) | Width C (mm) |
|---|---|---|---|---|---|---|
| 1051-44RC | 4.80 | 121.92 | 4.39 | 111.51 | 3.94 | 100.08 |
| 1051-45RC* | 5.00 | 127.00 | 5.52 | 140.21 | 3.97 | 100.84 |
| 1051-46RC* | 4.75 | 120.65 | 6.60 | 167.64 | 5.74 | 145.80 |
| 1051-55RC* | 5.90 | 149.86 | 5.50 | 139.70 | 5.92 | 150.37 |
| 1051-64RC* | 6.95 | 176.53 | 4.38 | 111.25 | 5.92 | 150.37 |
| 1051-65RC* | 6.95 | 176.53 | 5.50 | 139.70 | 5.92 | 150.37 |
| 1051-66RC | 6.95 | 177 | 6.60 | 168 | 6.0 | 152 |
| 1051-86RC* | 9.05 | 229.87 | 6.38 | 162.05 | 5.89 | 149.61 |
| 1051-8-10RC* | 10.63 | 270.00 | 9.05 | 229.87 | 5.89 | 149.61 |
| 1051-88RC | 9.25 | 234.95 | 8.51 | 216.15 | 5.97 | 151.51 |
| 1051-10-8RC* | 11.02 | 279.91 | 8.38 | 212.85 | 5.97 | 151.51 |
| 1051-1210RC* | 13.30 | 337.82 | 10.60 | 269.24 | 5.97 | 151.51 |
| 1051-1212RC* | 13.37 | 339.60 | 12.60 | 320.04 | 5.97 | 151.51 |
| 1051-1818RC | 19.74 | 501.27 | 19.74 | 501.40 | 9.89 | 251.28 |
* Supplied with reducer.
Maximum Test Pressure: 4.3 PSI (29.6 KPA)
Maximum Operating Temperature: 140° F non-consistent
1055 Series - Ductile Iron to Ductile Iron
| Part No. | Side A (in) | Side A (mm) | Side B (in) | Side B (mm) | Width C (in) | Width C (mm) |
|---|---|---|---|---|---|---|
| 1055-44RC | 4.75 | 120.65 | 4.75 | 120.65 | 3.96 | 100.58 |
| 1055-66RC | 6.65 | 168.91 | 6.65 | 168.91 | 5.92 | 150.37 |
| 1055-88RC | 9.05 | 229.87 | 9.05 | 229.87 | 5.98 | 151.89 |
| 1055-1010RC | 11.22 | 284.99 | 11.22 | 284.99 | 5.97 | 151.51 |
| 1055-1212RC | 13.37 | 339.60 | 13.37 | 339.60 | 5.97 | 151.64 |
* Supplied with reducer.
Maximum Test Pressure: 4.3 PSI (29.6 KPA)
Maximum Operating Temperature: 140° F non-consistent
1056 Series - CI, PL, or ST to CI, PL, or ST
| Part No. | Side A (in) | Side A (mm) | Side B (in) | Side B (mm) | Width C (in) | Width C (mm) |
|---|---|---|---|---|---|---|
| 1056-150RC | 1.94 | 49.28 | 1.94 | 49.28 | 3.43 | 87.12 |
| 1056-22RC | 2.41 | 61.21 | 2.41 | 61.21 | 3.45 | 87.63 |
| 1056-32RC* | 3.52 | 89.41 | 2.38 | 60.45 | 3.96 | 100.58 |
| 1056-33RC | 3.46 | 87.88 | 3.46 | 87.88 | 3.98 | 101.09 |
| 1056-43RC* | 4.58 | 116.33 | 3.38 | 85.85 | 4.02 | 102.11 |
| 1056-44RC | 4.58 | 116.33 | 4.58 | 116.33 | 4.02 | 102.11 |
| 1056-54RC* | 5.52 | 140.21 | 4.38 | 111.25 | 3.97 | 100.84 |
| 1056-55RC | 5.52 | 140.21 | 5.52 | 140.21 | 3.97 | 100.84 |
| 1056-64RC* | 6.60 | 167.64 | 4.50 | 114.30 | 5.74 | 145.80 |
| 1056-65RC* | 6.60 | 167.64 | 5.62 | 142.75 | 5.74 | 145.80 |
| 1056-66RC | 6.60 | 167.64 | 6.60 | 167.64 | 5.74 | 145.80 |
| 1056-86RC* | 8.64 | 219.46 | 6.38 | 162.05 | 6.04 | 153.42 |
| 1056-88RC | 8.64 | 219.46 | 8.64 | 219.46 | 6.04 | 153.42 |
| 1056-1010RC | 10.63 | 270.00 | 10.63 | 270.00 | 5.89 | 149.61 |
| 1056-1212RC | 12.52 | 318.01 | 12.52 | 318.01 | 6.32 | 160.53 |
| 1056-1515RC | 15.92 | 404.37 | 15.92 | 404.37 | 9.89 | 251.21 |
| 1056-1818RC | 19.10 | 485.14 | 19.10 | 485.14 | 9.89 | 251.21 |
* Supplied with reducer.
Maximum Test Pressure: 4.3 PSI (29.6 KPA)
Maximum Operating Temperature: 140° F non-consistent
Frequently Asked Questions
Quick answers for selection, use and compliance.
What is a Strong Back RC Coupling used for?
Strong Back RC Couplings are used for underground pipe transitions where added shear resistance, alignment support and reliable sealing performance are needed.
What makes Strong Back RC different from a standard flexible coupling?
Strong Back RC Couplings include a stainless steel shear ring and molded-in bushing to provide added support for underground applications exposed to heavy earth loads and pipe movement.
Which pipe materials can Strong Back RC Couplings connect?
Available series support transitions involving clay, cast iron, plastic, concrete, ductile iron and steel piping. Always choose the correct series and size based on the outside diameter of each pipe.
Are Strong Back RC Couplings AIS and BABA compliant?
Strong Back RC Couplings 15 inches and below are Made in the USA and AIS/BABA compliant. Refer to the product listing or Fernco AIS/BABA information for confirmation on specific sizes.
How do I choose the correct part number?
Match the pipe material transition first, then confirm the outside diameter for Side A and Side B in the part-number table. If the pipe type or outside diameter is uncertain, contact Fernco for sizing support.
What is the installation torque?
Strong Back RC Couplings are installed at 60 in-lbs. Always follow the latest Fernco installation instructions.