The MP17 from FLUX Defense is a brace that transforms a SIG Sauer P320/M17 handgun into a PDW (personal defense weapon) designed to shoot like a carbine and holster like a pistol. While previous FLUX brace models only fit Glock pistols, the new MP17 is a grip module that fits the Army’s newly adopted M17 pistol and the P320 civilian version. It could provide the crossover so desperately needed between the two platforms.

Until now, most pistols and PDWs shared little—if any—common traits. This required the user to carry two different kinds of magazines and spare parts for the two different platforms.

FLUX MP17 brace
The author firing a SIG Sauer P320/M17 with the new FLUX MP17 brace grip module attached. T. Logan Metesh

The FLUX MP17 changes all of that. They didn’t actually make a new firearm. Instead, they have made a new firearm host. The MP17 takes the fire control module, barrel, and slide of an M17/P320 and places them into the FLUX chassis. Once installed, you’ve now got a PDW that is optics-ready, has a spring-loaded arm brace that deploys with one finger, and has a storage spot in the front of the chassis for storing an extra magazine (don’t dare call it a foregrip).

All of this is certainly appealing to the civilian market because it allows P320 shooters to streamline their options and platforms, but it could be a game-changer for the military if they chose to add the MP17 to their list of equipment.

FLUX G17 brace
The original FLUX brace attached to a Glock G17 with the brace collapsed. The spring-loaded brace extends with the push of a lever activated by the shooter’s trigger finger. Joseph Albanese

The concept of what FLUX is doing is not new. Adding a brace to a pistol that allows it to be fired from the shoulder is centuries old. The folks at FLUX know that, and know that they’re not coming up with something the likes of which has never been seen. They’re not trying to reinvent the wheel; rather, they just want to make it roll more smoothly.

MSRP for the FLUX Defense MP17 is $399. The specially-designed holster for the chassis is $199.