28 gauge

Photo coming soon: side view on a transparent background, with author and license.

Key specs

Type: Shotgun
Gauge: 28 gauge
Bullet diameter: 13.97 mm

Weapons chambered for it 2

ShotgunsMossberg SA-2020 gauge, 28 gaugeUnited States · 2008

ShotgunsRuger Red Label12 gauge, 20 gauge, 28 gaugeUnited States · 1977

Sources

Wikipedia: Gauge (firearms), Wikipedia