Beer Fitting Identifier & Reference Guide
Sankey Fitting & Thread Identifier
Draft beer systems use a confusing mix of fittings — MFL, barb, flare, NPT, ball lock, and push-in — and using the wrong one causes leaks, foam, and contamination. Select what you're connecting below and we'll tell you exactly which fitting and thread spec you need.
Why fitting identification matters
A wrong fitting is the difference between a perfectly poured pint and a foamy mess. CO2 tanks use CGA-320 left-hand threads that strip if you force a right-hand fitting. Faucets universally use 5/8"-18 UNF. Gas lines use 1/4" MFL or barb. Getting the fitting right means leak-free connections and beer that tastes as intended.
What Are You Trying to Connect?
Complete Thread & Fitting Reference
| Fitting Name | Thread / Spec | Used For | Material | Notes |
|---|---|---|---|---|
| CGA-320 | 0.965"-14 Left-Hand | CO2 tank valve to regulator | Brass | Left-hand thread — turn counter-clockwise to tighten |
| 5/8"-18 UNF | 5/8"-18 UNF | Faucet to shank (industry standard) | Stainless/Brass | Universal for all standard draft faucets |
| 3/4"-14 NPT | 3/4"-14 NPT | Shank through door or wall | Stainless/Brass | Use thread sealant on NPT threads |
| 1/4" MFL (Female Flare) | 7/16"-20 UNF | Gas line connections, manifold | Brass | Most common gas fitting in draft systems |
| 1/4" Barb | Barb (no thread) | Gas line to coupler, regulator | Brass/Nylon | Secure with worm clamp or crimp |
| 3/16" Barb | Barb (no thread) | Beer line (standard) | Stainless | Most common beer line connection; use swivel barb for easy removal |
| 1/4" Barb | Barb (no thread) | Beer line (high-flow/direct draw) | Stainless | Lower restriction than 3/16" |
| Ball Lock — Gas (Gray) | Ball lock quick-connect | Cornelius keg gas inlet | Stainless/Plastic | Gray color = gas (in) |
| Ball Lock — Beer (Black) | Ball lock quick-connect | Cornelius keg beer outlet | Stainless/Plastic | Black color = beer (out). NOT interchangeable with gray. |
| Pin Lock — Gas (2-pin) | Pin lock quick-connect | Older Cornelius keg — gas in | Stainless | 2 pins = gas; 3 pins = beer on pin lock kegs |
| Duotight Push-In | Push-in (no thread) | Flexible line connections, long draw | Stainless/Plastic | Tool-free — just push tubing in, pull collar to release |
| John Guest Push-In | Push-in (no thread) | Gas and beer line fittings | Plastic/Brass | Popular in glycol systems and long draw installations |
Frequently Asked Questions About Draft Beer Fittings
What thread does a draft faucet use?
Every standard draft faucet uses 5/8"-18 UNF thread. This is the universal standard for all draft faucets in the US — Perlick, Intertap, standard chrome, stout faucets, and flow-control models all use the same shank thread. If your shank uses this thread, any faucet in our catalog will fit.
How do I know if a fitting is left-hand or right-hand thread?
CO2 tank connections (CGA-320) use left-hand threads — turn counter-clockwise to tighten. Most other threads in draft systems (MFL, NPT, UNF) are right-hand — turn clockwise to tighten. Force is the warning sign: if a fitting won't thread easily by hand, you're likely going the wrong direction or using the wrong size.
Can I use brass fittings for beer contact?
No — brass contains lead and can react with acidic beer. Use stainless steel for all beer-contact fittings: barbs, shanks, tailpieces, and connectors. Brass is acceptable for gas-side connections only (CO2 fittings, manifold components, regulator connections) where there's no direct beer contact.
What size barb fitting do I need for 3/16" beer line?
3/16" ID beer line uses a 3/16" barb fitting. The barb outer diameter should match the tubing inner diameter. For 1/4" line, use 1/4" barbs. Stainless steel swivel barb fittings are recommended for beer lines because they make disconnection for cleaning much easier than fixed barbs.
What's the difference between MFL and NPT threads?
MFL (Male Flare) uses 7/16"-20 UNF threads and seals via a flared metal-to-metal surface — no thread sealant needed. NPT (National Pipe Thread) uses tapered 3/4"-14 threads that seal by wedging the threads together, requiring thread sealant tape or pipe dope. MFL is common on gas connections; NPT is used for shanks through holes.
Can I use PTFE tape on MFL or flare fittings?
No — never use PTFE tape on flare or MFL fittings. Flare fittings seal on the angled metal surfaces, not the threads. PTFE tape on flare threads can prevent proper metal-to-metal sealing, causing leaks. PTFE tape is appropriate for NPT threads only, applied to the male thread in the direction of tightening (typically 3–4 wraps).
Need the right fitting for your draft system?
We stock stainless and brass fittings in every size — barbs, swivel nuts, tailpieces, MFL adapters, flare nuts, push-in fittings, and hose plugs. Same-day shipping from the Northeast for bars, breweries, and installers.
Shop All Draft FittingsWholesale pricing available for volume orders. Call 800-821-0114 for custom fitting packs.