- Fernco couplings are used for all types of in-house and sewer connections: drain waste, vent piping, house-to-main repairs, cut-ins, conductor and roof drains and increasers-reducers.- Made of touch elastomeric polyvinyl chloride (PVC), they are strong, resilient and unaffected by soil conditions. They are also resistant to chemicals, ultravoilet rays, fungus growth, and normal sewer gasses due to the inert nature and physical properties of the material.- Fernco couplings are leakproof, rootproof and seal against infiltration and exfiltration.- Other sizes and types available - call for prices.