Hi Erick, this has a 4.49" fluted stainless barrel. To reduce weight, BUL Armory gave the slide a weight reduction cut and also added fluting to the barrel.
Stay safe & have a great day!

The bul armory axe tomahawk fs features a fluted barrel and optic ready cut slide.The slide also features flared magwell with side cuts & 3-dot steel sights.Its frame has high grip beavertail, reversible mag release, ambidextrous thumb rest & 1913 picatinny rail.
Frame Finish: Black
Action: Striker Fire
Caliber: 9mm Luger
Barrel Length: 4.49"
Capacity: 17+1
Safety: Manual Thumb, Beavertail Grip
Grips: Aggressive Textured Black Polymer
Sight Configuration: 3-Dot
Slide Description: Serrated Sliver Stainless Steel with Optic Cut

Hi Eric and welcome. The barrel is a 4.49" Fluted Stainless Barrel. The Barrel is not ported.
BUL Armory Axe FS Tomahawk Specifications and Features:
BUL Armory USA Item Number: AXEFSTOMASLV9US
Full Size Semi-Automatic Pistol
Striker Fired
Caliber: 9mm Luger
17 Rounds
4.49" Fluted Stainless Barrel
Optics Ready Slide (Trijicon RMR Footprint)
Polymer Frame
Integrated Flared Magazine Well
High Grip Beavertail
Double Undercut Trigger Guard
Aggressive Grip Texturing
Reversible Magazine Release
Extended Slide Lock Lever
Ambidextrous Thumb Indexing Points
Flat Face Trigger
3.5 - 4 lb Trigger Pull
1913 Picatinny Rail
Aluminum Guide Rod
Dimpled Stainless Steel Pin Kit
Tomahawk Slide Serrations with Weight Reduction Cut
Steel 3-Dot Sights
Weight (without magazine): 23.63 oz
Color: Silver Slide, Black Frame
Cheers and stay safe!