The Marshall Excelsior MER401-24 is a 24-inch flexible LP gas pigtail hose built for RV propane systems. With a POL 7/8" left-hand nut on the tank end and a 1/4" male inverted flare on the appliance end, this hose is engineered for reliable, code-compliant connections at the cylinder. The integrated excess flow feature adds a critical layer of safety, limiting gas flow automatically if the downstream line is severed or damaged.
Pigtail hoses are the flexible link between your fixed LP cylinder and the rigid copper or steel distribution lines in your RV. Unlike hard-plumbed fittings, a pigtail absorbs vibration and slight movement during travel, reducing stress on your regulator and tank valve. The MER401-24 is a workhorse in this role -- a 24-inch length that suits most standard dual-cylinder RV setups, campers, and portable propane applications.
Marshall Excelsior has manufactured LP gas equipment in Michigan since 1943. The MER401-24 reflects that pedigree: fully crimped brass ferrules at both ends, a UL-listed and CGA-approved thermoplastic hose body, and built-in thermal protection. Every hose ships ready to install -- no loose parts, no assembly required.
Integrated excess flow valve automatically restricts LP flow if a sudden downstream surge is detected -- an important safety feature for unattended or hard-to-monitor installations.
Rated for 350 PSIG working pressure, well above the typical 11" W.C. service pressure of an RV LP system, with substantial safety margin built in.
Both ends are factory-crimped with brass ferrules -- no hose clamps, no field assembly. Crimped construction maintains a leak-free seal over years of use and vibration.
The flexible thermoplastic hose body carries UL listing and CGA approval, meeting the certifications required for LP gas connections in RV, residential, and commercial applications.
Getting the fittings right is the single most important part of buying a pigtail hose. This hose has two distinct ends:
The excess flow mechanism is housed inside the POL fitting body. Under normal operating conditions, gas flows freely at the low pressure and volume demanded by RV appliances. If downstream flow suddenly exceeds the preset threshold -- such as when a downstream line ruptures or a fitting is disconnected while the cylinder valve is open -- the valve seats itself, reducing flow to a trickle. This limits the volume of unburned propane released into the environment.
The MER401-24 includes built-in thermal protection on the hose assembly. In the event of fire or sustained high external heat near the hose, the thermal protection is designed to limit LP flow, reducing the risk of continued fuel supply to a fire source. This feature is required by some codes for enclosed or semi-enclosed LP installations.