MIL-PRF-131L Class 1 MIL-SPEC Bags, Pouches & Packaging

MIL-PRF-131L Class 1

MIL-PRF-131L Class 1, which formally supersedes the older MIL-PRF-131K, MIL-PRF-131H, and MIL-PRF-131J standards, defines the Department of Defense performance requirements for heat-sealable, greaseproof, flexible barrier materials. While the specification has evolved, the core mission, providing robust protection for military assets against the most hostile storage and shipping environments, remains the same.

As a leading MIL-PRF-131L Class 1 packaging manufacturer, the Caltex Plastics team engineers MIL-SPEC packaging solutions to exceed the general use requirements set by the Naval Air Warfare Center and the Defense Logistics Agency.

Protection Properties

Our CALPAC ULTRAFOIL series, specifically ULTRAFOIL 500M and 1000M, is QPL-listed and laboratory-tested to ensure it delivers these essential protection characteristics:

• Water vapor proof: A minimal moisture vapor transmission rate (MVTR) that prevents corrosion and oxidation during long-term storage or naval transfer.
• Greaseproof and oil resistant: A robust construction that exhibits no delamination, embrittlement, swelling, or leakage when exposed to solvents and oils.
• Faraday cage shielding: A buried metal construction that provides static shielding to safeguard sensitive electronics from electrostatic discharge (ESD).
• Physical durability: High tensile strength to resist puncturing, tearing, and rough handling during logistics operations.

We rigorously test our bags, pouches, and packaging to ensure adherence to MIL-PRF-131L Class 1 standards.

Features and Benefits

Whether you require the standard protection of CALPAC ULTRAFOIL 500M or the heavy-duty durability of CALPAC ULTRAFOIL 1000M, our products offer the following technical features and benefits:

• Static protection: Rugged buried-metal construction delivers Faraday cage performance to protect against static.
• Configuration options: Available in side-gusset, bottom-gusset, and T-Seal bag configurations to fit irregular parts.
• Closure systems: Available with zipper closures for reusability where permitted.
• Chemical purity: Polycarbonate compatible and contains no amines or N-Octanoic acids.
• Traceability: Thermal transfer and custom printing are available for lot codes and military identification markings.
• Rollstock availability: Available as J-fold roll stock for converters or automated packaging lines.

Applications

The primary application of MIL-PRF-131L Class 1 packaging is the preservation of items requiring a specialized microclimate. Because of its low MVTR and heat-sealability, this barrier material is the industry standard for Method 41 (Water Vapor Proof) and other military preservation methods.

You will frequently see this material specified for items destined for naval and naval aviation environments. Equipment in these theaters faces exposure to elevated salt spray concentrations, extreme humidity, and rough handling during transfer at sea. Caltex Plastics barrier packaging can withstand these extremes, ensuring that engines, generator parts, and avionics remain corrosion-free until deployment.

Buy MIL-PRF-131L Class 1 MIL-SPEC Bags, Pouches, and Packaging From Caltex Plastics

Caltex Plastics is a trusted authority in military barrier packaging. We do not just sell packaging. We manufacture QPL-listed materials that guarantee compliance. When you source from us, you get the certainty that your material meets the new MIL-PRF-131L specification, backed by our 24/7 operations and rapid delivery.

Contact Caltex Plastics today to request a quote or verify specs for your next military contract.