SIGM400 Tread pistol. MSRP: $951

This from their website:

The M400 TREAD pistol is an optics ready, aluminum receiver rifle caliber pistol. The TREAD pistol features a 11.5” Nitride Coated barrel with a free-floating M-LOK handguard, a single-stage polished/hard-coat trigger, ambidextrous controls, a Shockwave Blade multi position pistol brace, and is available in 5.56 NATO.

The TREAD branded accessories include:
- M-LOK handguard with lightening cuts to reduce weight, available in 11.5”;
- Ambidextrous charging handle made of aircraft grade aluminum and a dual roll pin design;
- ROMEO5 optic featuring a 2MOA dot with ten illumination settings, MOTAC, and 50k battery life;
- Flip-up front and rear iron sights that are easy to install, adjustable, and deploy quickly;
- M-LOK front sight adapter with co-witness height made of lightweight aluminum;
- Multiple configurations of M-LOK grip kits made of high strength polymer;
- Factory upgraded flat blade, single stage trigger.

OPERATING SYSTEM: Direct Impingement
CALIBER: 5.56 NATO
OVERALL LENGTH (IN): 27 in (686 mm)
OVERALL WIDTH: 2.5 in (64 mm)
HEIGHT: 7.5 in (191 mm)
BARREL LENGTH: 11.5 in (292 mm)
WEIGHT (OZ): 6 lbs (2.7 kg)
TWIST RATE: 1:7
MAG TYPE: AR-15