New SIG Sauer P365-Fuse, the largest and most capable P365 ever

A longer 4.3”/109 mm barrel and 21+1 capacity: SIG Sauer has just unveiled the new P365-Fuse, the largest model in the P365 series. It's not hard to understand why they gave it the name of “Fuse”: since the standard P365 barrel is 3.1”/78 mm long, and even the P365 XL comes with a 3.7”/94 mm barrel, with a max magazine capacity of 12 rounds, the latest SIG pistol is intended as a “fusion” of full-size capability and micro-compact concealment.

SIG Sauer P365-Fuse, also with  ROMEO-X red dot

SIG Sauer P365-Fuse, a fusion of capability and concealment
“The ultimate fusion of capability and concealment”: new SIG P365-Fuse pistol. Note the extended 21-round magazine.

Chambered in 9mm Luger, the striker-fired P365-Fuse features an optics-ready slide and the thin (1”, or 25 mm) polymer LXG (laser engraved X-grip) grip module. A 1913 accessory rail, removable magwell, interchangeable backstraps (small, medium, and large), and a nickel-plated flat-faced trigger are all onboard the new striker fired pistol from SIG. The long optics-ready stainless steel slide has aggressive serrations. Sights include a fiber optic front sight and a black serrated rear sight. The carbon steel barrel is DLC finished.

SIG P365-Fuse accessory rail and nickel-plated flat-faced trigger.
The SIG P365-Fuse has no manual safety. It features a 1913 accessory rail, removable magwell, interchangeable backstraps (small, medium, and large), and a nickel-plated flat-faced trigger.

The pistol is also available in the P365-Fuse ROMEO-X version, complete with a factory installed ROMEO-X compact sight crafted from 7075 aircraft-grade aluminum, machined anti-reflection grooves on shooter-facing surfaces, distortion-free aspheric glass, with a patent-pending Beryllium Copper flexure-arm adjustment system. 

The optics-ready slide of the SIG P365-Fuse
The 174-mm slide of the SIG P365-Fuse is optics-ready. The pistol comes with a fiber optic front sight and a black serrated rear sight.

The ROMEO-X optics incorporate both a MOA red dot and a 32 MOA circle reticle, side independent brightness adjustment buttons, and 15 brightness settings (including night vision settings). The low deck height allows for standard-height iron sight co-witness. 

MOTAC (Motion Activated Illumination), MAGNETAC™ (Magnetic Activation), and D.A.R.C. (Dark Adaptive Reticles & Coatings) technologies are all part of the ROMEO-X package. Prices for the P365-Fuse and P365-Fuse ROMEO-X are to be announced.

The new P365-Fuse is described as a true crossover carry gun, with its 174-mm optic-ready slide being longer than any compact in its class for improved sight radius and enhanced control. 

Even if a 21+1 capacity is undoubtedly attractive too, with the extended magazines footprint is pretty big, however. 

Sure, the gun also accepts shorter 17-round magazines. But with an overall length of 182 mm – more or less the same as the P320 Carry and Compact models – can it still offer “micro-compact concealment” as claimed by the manufacturer? Is longer always better? Let the market decide.

P365-Fuse technical specifications

Magazine Capacity:

21, 17 or 10 rounds

Barrel Length: 
4.3”/109 mm
Overall Length: 
182 mm
Overall Height: 
129 mm
Overall Width:  
28 mm
Sight Radius: 
152 mm
Optics Slide Cut: 
Weight (w/Magazine): 
655 g
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