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Marshall Excelsior · Fuel System
MEV300FIR/265
In stock · ships from Knoxville
The MEV300FIR/265 is a full internal relief valve manufactured by Marshall Excelsior.
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Designed for mobile containers with a 3" MPT tank opening that require a 265 PSI relief setting. Always verify your tank’s pressure rating and connection type before installation.
Part data verified against 5 catalog sources
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It serves as the primary pressure relief device on mobile LPG (propane) and anhydrous ammonia (NH3) tanks, such as those found on bobtail delivery trucks and transport trailers. The valve automatically opens at 265 PSI to safely vent excess pressure, protecting the tank from overpressurization. This model features a 3-inch MNPT threaded inlet and nitrile seals, and is typically replaced when it no longer holds pressure, leaks, or during scheduled maintenance to ensure reliable overpressure protection.
Part Number: MEV300FIR/265
3 MNPT FULL INTERNAL RELIEF VALVE 265PSI, NITRILE
Unit: ea
Dealer: Post Onsite
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