Bridges the gap between older POL-valve propane cylinders and modern Type 1 (ACME) connectors. Installs into the cylinder's POL valve outlet and presents a male Type 1 thread — allowing a Type 1 pigtail or regulator hose to connect directly. Also adapts 50 lb and 100 lb cylinder fittings to male Type 1 thread. Brass construction.
The propane industry has largely transitioned from the older POL (Prest-O-Lite) left-hand-thread valve connection to the modern Type 1 (ACME) connector — but older cylinders, 50 lb cylinders, and 100 lb cylinders often still use POL valves. If your pigtail or regulator supply hose has a Type 1 connector and your cylinder has a POL valve, the MB Sturgis 204128-MBS is the adapter that bridges the two.
The adapter threads into the POL valve on the cylinder using a soft nose POL male fitting — the left-hand-thread connection standard for POL valves — and presents a male Type 1 (ACME) thread on the other end, allowing a Type 1 pigtail hose to screw on just as it would on a cylinder with a native Type 1 valve. It's also useful for adapting a 50 lb or 100 lb cylinder with a POL fitting to accept a standard Type 1 regulator hose. Machined from brass, the 204128-MBS is built for reliable sealing in propane gas applications.
Bridges POL-valve cylinders to Type 1 pigtail hoses and regulators — no need to replace the cylinder or the hose
Soft nose POL fitting threads into the cylinder's POL valve using left-hand thread — standard for POL connections
Presents a male Type 1 ACME thread, allowing any standard Type 1 pigtail or supply hose to attach directly
Precision brass fitting for reliable sealing and long-term durability in propane gas applications
The soft nose POL end of this adapter uses left-hand thread — the standard for POL propane fittings. This means you turn it counter-clockwise to tighten into the cylinder's POL valve, and clockwise to loosen (the opposite of standard right-hand threads). This is intentional and not a defect — left-hand thread is a safety feature on propane connections to prevent accidental loosening during use, and to make it physically impossible to connect to non-propane gas lines that use standard right-hand threads. The Type 1 end of this adapter uses standard right-hand thread — your Type 1 pigtail or regulator hose tightens clockwise as normal.
1. Older 20 lb Cylinder with POL Valve: If you have an older 20 lb cylinder that has a POL valve instead of the modern Type 1 valve, install this adapter in the POL outlet so your Type 1 pigtail hose can connect to it — without needing to replace or re-valve the cylinder. 2. 50 lb or 100 lb Cylinder: Large 50 lb and 100 lb propane cylinders typically use POL fittings rather than Type 1 valves. This adapter converts the POL outlet to accept a standard Type 1 regulator supply hose or pigtail, making these large cylinders easier to use with modern equipment. 3. Generator Hookups: Generators that include a Type 1 supply hose can use this adapter to connect to a 100 lb cylinder with a POL valve — a common setup for extended off-grid power supply. Note: Two adapters may be needed for dual-cylinder generator or heating setups — one per tank.
Installation Steps: 1. Close Tank Valve: Ensure the cylinder's tank valve is fully closed before installing or removing any fittings 2. Thread POL End Into Cylinder: Insert the soft nose POL end of the adapter into the cylinder's POL valve outlet — turn counter-clockwise to tighten (left-hand thread) 3. Hand-Tighten POL Connection: POL fittings are typically hand-tightened only — do not use a wrench on the POL side unless specified 4. Connect Type 1 Pigtail: Thread your Type 1 pigtail hose connector onto the adapter's male Type 1 end — turn clockwise to tighten (standard right-hand thread) 5. Leak Test: Slowly open the tank valve and perform a soap-and-water leak test on all connections before use Gas fittings and connections should be verified by a qualified technician. Always leak-test before placing the system into service.
In The Package: • (1) 204128-MBS Propane Adapter Fitting — Male Soft Nose POL x Male Type 1 (ACME) NOT Included: • Type 1 pigtail or regulator supply hose (sold separately) • Thread sealant (not required for POL connections; confirm for Type 1 side based on application)
MB Sturgis Technical Support: Phone: (314) 291-6665 Email: [email protected] MB Sturgis Inc. has supplied OEMs, distributors, gas installers, and end users with safe LP and natural gas connection products since 1959.