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Flexible Boss Junction

The faster and lower cost method of making sewer main connections.

Boss Junction WebOne Fernco Boss Junction will fit ALL 6" and larger sewer mains. Available for all 4" or 6" plastic or cast iron drain pipe inlets in 90° or 45° configurations.


  • Manufactured from a specially formulated high durometer PVC
  • Rigid, yet flexible enough for one saddle to fit 6" or larger sewer mains
  • Includes special "slip-lock" clamps of 300 series stainless steel that make for fast and simple installations on any type of pipe from 6" to 15"
  • Larger apron with locating ring fits 4½" or 6½" standard shell cutters
  • Large band grooves 
  • Leak-proof, root-proof and are resistant to chemicals, ultraviolet rays, fungus growth, and normal sewer gases
  • Conforms to ASTM #D5926, C1173 and applicable portions of ASTM #C443, C425, C564, CSA B602 and D1869
  • Maximum test pressure: 4.3 PSI (29.6KPA)
  • Maximum operating temperature: 60º C non-consistent


  • TST-4 - 4" 90° Boss Junction
  • TST-6 - 6" 90° Boss Junction
  • TSW-4 - 4" 45° Boss Junction
  • TSW-6 - 6" 45° Boss Junction
  • 312-300 - Extension Clamps - For larger than 15" sewer mains
  • TSPK-46 - Pressure Kit for Flexible Boss Junction

Bentonite tape provides for a water tight seal. Pressure tested to hold 10 PSI. Rubber coated steel reinforcing bars apply even sealing pressure. Two 300 series stainless steel clamps are "Slip-Lock" for fast and easy installation.