Buying Guide

Gas and Water Supply Lines

Type of Supply Line

Follow these steps to determine the supply line you need:   

  • Measure the distance between the appliance and the gas supply and add three inches to be sure it’s long enough. 
  • Refer to the manufacturer’s label on the appliance to identify the maximum gas input rating. 
  • Select a flexible supply line with a maximum flow rating capacity higher than the appliance’s input rating. 
  • Select the supply line with the connectors that match the appliance’s gas shut-off valve and inlet.
Gas Supply Materials

Gas supply are usually used for clothes dryers, water heaters, gas ranges and fireplaces, and they are usually made out of copper or braided stainless steel covered with a sturdy plastic coating.

Gas Supply Connectors

Typically measured by outer diameter, which is designated as “OD” on packaging. Common examples include:  

  • Dryers – 3/8” stubout MIP 
  • Water Heaters – ½” FIP inlet 
  • Gas Ranges – ½” FIP inlet 
  • Gas Fireplaces – 3/8” stubout MIP or 3/8” flare fitting
Water Supply Line Materials

May be made of copper, but most are made of plastic, braided plastic or braided stainless steel. Research local regulations because some areas do not allow braided plastic supply lines.

Water Supply Connectors

To select the right connector, follow these steps:  

  • Determine the length you need by measuring from the inlet valve to the fixture, then add 4” to make sure it’s long enough. 
  • Select the connector size. Refer to the list below as a general guide.


  • Connector at Fixture: 3/8" male pipe  
  • Connector at Shut-Off Valve: 1/2" or 3/8" compression


  • Connector at Fixture: 1/2" female pipe  
  • Connector at Shut-Off Valve: 1/2" or 3/8" female compression or sweat


  • Connector at Fixture: 1/4" female compression  
  • Connector at Shut-Off Valve: 1/4" female compression


  • Connector at Fixture: 7/8" ballcock  
  • Connector at Shut-Off Valve: 1/2" or 3/8" female compression or sweat

Washing Machine  

  • Connector at Fixture: 3/4" hose thread  
  • Connector at Shut-Off Valve: 3/4" hose thread

Refer to the following designations on the packaging and labels to select the supply line you need:  

  • NPT (National Pipe Tapered Threads). Industry standard for tapered threads used to join pipes and fittings. 
  • FPT or FIP (Female Pipe Thread). Female threaded fitting with the threads on the inside. 
  • MPT or MIP (Male Pipe Thread). Male threaded fitting with threading on the outside. 
  • Compression. Fitting that attaches to a standard compression thread on the valve.
  • Water Hammer Arresters. Also known as mufflers. Stops the banging sound you hear when valves on washing machines, dishwashers and faucets slam shut. Also prevents damage to pipes and faucets. 
  • Corrosion Resistance. Built-in protection against corrosion. 
  • Deep Corrugation. Provides greater flexibility. 
  • No-Burst Hoses. Reinforced with stainless steel braiding. 
  • Right-Angle Connectors. Ideal for installing a supply line in tight areas without kinks or breaks.
Product Innovations

FloodSafe™ Connectors ensure proper pipe fit and operation and automatically shut off when a preset specified water flow amount has been exceeded. Protects homes from water damage.