The Sig P365 FUSE is a 9mm semi-automatic pistol with a 4.3-inch barrel and an optic-ready cut. It ships with polymer grips, a Marine Cerakote metal finish in Debo Green, and fiber optic sights. Magazine options include a 17-round and two 21-round magazines. 
 

Key Specifications 

• Brand: Sig Sauer 
• Model: P365 FUSE 
• Caliber: 9mm 
• Action: Semi Auto 
• Capacity: 17 and 21 rounds 
• Barrel Length: 4.3 in 
• Color/Finish: Debo Green (Marine Cerakote) 
   

Detailed Features 

• Optic-ready slide cut 
• Marine Cerakote finish on metal components 
• Fiber optic sights 
• Polymer grips 
• Ships with 17-round and 21-round magazines

Owners of the P365 FUSE appreciate the longer barrel and higher-capacity magazines compared to the standard P365, while the platform still shares the same ergonomics and parts ecosystem. The Debo Green Cerakote finish draws attention at the range and is regularly cited as a reason for purchase.

The optic-ready cut and included fiber optic sights give buyers flexibility. Many run the irons as delivered and find them accurate; others mount a compact red dot immediately. The fiber optic front in particular gets positive marks in low-light conditions.

The trigger divides opinions similarly to other P365 variants: it is consistent and short but some owners find the reset less tactile than they prefer. Magazine capacity is a recurring positive, with the 21-round option making the FUSE feel more like a compact duty pistol than a carry gun.