How it connects
The cut CSST tubing is inserted into a flange nut with a split brass retainer ring seated in a corrugation valley. Threading the nut onto the male fitting body compresses the tube end against a flat non-metallic gasket to form a gas-tight seal.
Male and female halves
Female termination/nut interface that receives corrugated stainless steel tubing (tubular male end) and threads onto the male fitting body or flange base.
Usually connects to
- HOME-FLEX Corrugated Stainless Steel Tubing (CSST)
- HOME-FLEX CSST male fitting adapter
Common sizes
- Nominal HOME-FLEX CSST sizes: 1/2, 3/4 and 1 in.
Where it is used
residential plumbingnatural gas pipingpropane pipingresidential fuel gas pipingcommercial natural gas and propane systems
Variations
- Termination flange
- Male adapter
- Female adapter
- CSST union coupling
- 1/2 in. CSST fitting
- 3/4 in. CSST fitting
How to recognise it
Recognized by a wide hex or flanged brass nut housing a split brass C-clip retainer ring, designed to clamp over the valley of a yellow-jacketed corrugated stainless steel gas pipe against a flat gasket inside the fitting.
Often confused with
| Confused with | How to tell them apart |
|---|---|
| TracPipe / Gastite / Pro-Flex CSST fittings | Different proprietary retainer ring, O-ring, and gasket geometry; CSST fittings and rings are not interchangeable across brands. CSST fittings and corrugation pitches are manufacturer-specific and non-interchangeable; HOME-FLEX uses a unique split brass retainer ring and flat sealing gasket system. |
| Gastite / FlashShield CSST fitting | Gastite uses a metal-to-metal flare mechanical clamping mechanism without a non-metallic flat gasket. |
| NPT pipe thread | CSST fitting threads accept proprietary brand-specific nuts and retainer rings to compress corrugated tubing onto a gasket rather than standard pipe threads. HOME-FLEX CSST nut uses straight machine threads and houses a split ring and gasket rather than tapered sealing threads. |
Also called
HOME-FLEX CSST fitting socketHOME-FLEX CSST termination portHOME-FLEX CSST mechanical fitting endHOME-FLEX CSST flange nut endHOME-FLEX CSST female termination
Good to know
CSST fittings and components are brand-proprietary under ANSI LC 1 / CSA 6.26 and must not be interchanged across manufacturers (e.g. HOME-FLEX fittings only mate with HOME-FLEX CSST tubing).
Related connections
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