20 Gauge Round

 is a type of ammunition in Fallout: New Vegas.

Used in

 * Sturdy caravan shotgun
 * Caravan shotgun
 * Lever-action shotgun
 * Single shotgun

Variants
20-Gauge Slug -- Fires a solid metal projectile to ensure maximum damage at greater distances. The in-game shell description notes the reduced spread, but fails to mention that it increases the projectile damage, and reduces the number of projectiles fired; this can make the value of slug shells less readily-apparent.
 * Value - 2
 * Gun Spread - x0.35
 * Damage - 43
 * Projectiles - 1

20-Gauge Magnum buckshot -- Magnum caliber shells hold more powder, resulting in higher muzzle velocity, which inflicts more harm on your victims. Unfortunately, the extra blasting power also deteriorates your shotguns that much faster.
 * Gun CND x 1.15
 * DAM x 1.15

Appearances
only appears in Fallout: New Vegas.