Flux Defense Introduces the Raider P365 Ultralight: Performance Without the Weight Penalty

Flux Defense transformed and revolutionized the P320 platform with the original Flux MP-17 and its later evolution, the Flux Raider. Following the monumental success of that chassis system, Flux turned its attention to SIG Sauer’s immensely popular P365 series, ultimately developing the Flux Raider P365.

The Raider P365 proved to be a genuine game changer in both the concealed carry and personal defense weapon (PDW) spaces. It blurred the traditional boundaries between handgun and PDW, allowing the platform to function effectively as both. This dual-role capability delivered a level of versatility that had previously been unavailable to end users in such a compact form factor.

Now, Flux Defense is introducing the next evolution of the Raider P365 family: the Raider P365 Ultralight. While it retains the proven architecture of the P365-based chassis system, the Ultralight transitions from aluminum construction to a high-strength polymer chassis. This shift significantly reduces overall platform weight while maintaining the performance and functionality that define the Raider series.

Polymer Construction, Purpose-Driven Weight Reduction

The defining feature of the Ultralight variant is its transition from an aluminum chassis to a polymer construction. This shift dramatically reduces overall system weight while maintaining the functional architecture that made the Raider platform successful.

Flux states that the Ultralight configuration delivers approximately 85% less weight and a platform roughly three inches shorter than an MP5K with a folding stock or sling setup, positioning it firmly in the niche between traditional concealed carry and compact PDW capability.

The intent is clear: maximize portability without sacrificing shootability.

Designed for Versatile Carry

Unlike many PDW-style platforms that lean toward overt deployment roles, the Raider P365 Ultralight was engineered with real-world carry considerations in mind. The system can be carried:

• Inside-the-waistband (IWB)

• Outside-the-waistband (OWB)

• Off-body in a sling bag or backpack

This flexibility allows users to maintain a familiar handgun manual of arms while gaining the stability advantages of a chassis system. The ability to effectively double onboard ammunition capacity thanks to extended magazines further reinforces the platform’s defensive utility.

Retaining the Raider DNA

Despite the material change, Flux preserved the hallmark features that defined the original Raider experience:

• Spring-loaded brace/stock deployment system

• Suppressor clearance capability

• Patented Speeloader magazine storage system

• Integrated chassis ergonomics designed for control and rapid follow-up shots

These features are not gimmicks they are functional enhancements that contribute directly to performance under stress.

Included Accessories and Options

The Raider P365 Ultralight ships with several accessories to tailor the system to user needs:

• Removable shroud

• Holster

• Optional flared magwell

• Optional 6-inch barrel (for increased velocity and ballistic performance)

The longer barrel option is particularly noteworthy, as it allows users to extract additional performance from defensive ammunition without moving to a larger firearm platform.

Compatibility Considerations

Flux provides clear guidance on configuration:

• Recommended slides: P365 XL, TACOPS, or P365 Fuse

• Not compatible: Standard P365 slides

• Magazine compatibility: 17-, 21-, and 25-round P365 magazines

• Suppressor clearance: Compatible with the majority of suppressors

• Magwells: Original aluminum Raider magwells are not compatible

These details matter, especially for users attempting to build optimized defensive systems rather than simple range setups.

A Continued Refinement of the Concept

The Raider P365 Ultralight represents a logical progression rather than a radical departure. Flux has taken a proven architecture and focused on improving portability, weight, and adaptability while maintaining the features that made the platform compelling in the first place.

In many ways, it reinforces a broader industry trend: the convergence of handgun concealability with carbine-like control.

The Raider P365 Ultralight is available now through Flux Defense’s website in black and FDE, with a stated 1–2 week lead time. MSRP is $499.

For more information on the Raider series and other Flux products, visit the company’s website.