Shotgun mod

There are five types of mod for shotguns, each providing a different benefit. Four are available in singleplayer and one is exclusive to multiplayer. For each type, there is one basic mod and two upgrades which provide a greater benefit, but with detrimental effects. Only the basic mods are available at the first tier in singleplayer.

With the exception of the Scattershot and Venom, a shotgun developed with a Double Mod Extension can take one of every type of mod.

Barrel

 * Shotgun Barrel: Enhances a weapon's barrel, creating greater gunfire velocity and impact.
 * Shotgun Long Barrel: Substantially increases damage, but at the cost of accuracy.
 * Shotgun Short Barrel: Substantially increases damage, but at the cost of increased recoil.

An equipped barrel mod changes the silhouette of a weapon.

Choke
Shotgun Chokes are only available for use in multiplayer.
 * Shotgun Smart Choke: Adjustable servo motors tighten or loosen pellet spread for maximum accuracy.
 * Shotgun Heavy Choke: Substantially increases accuracy, but at the cost of fire rate.
 * Shotgun Light Choke: Substantially increases accuracy, but at the cost of reload speed.

The Dhan and N7 Crusader cannot be equipped with a choke.

An equipped choke mod changes the color of parts of a weapon to a dull brown.

Clip

 * Shotgun Spare Clip: Adds sockets to increase thermal clip capacity, increasing number of spare shots.
 * Shotgun Asymmetric Spare Clip: Substantially increases ammo capacity, but at the cost of reduced melee damage.
 * Shotgun Heavy Spare Clip: Substantially increases spare ammo, but at the cost of accuracy.

The Scattershot cannot be equipped with a spare clip.

An equipped spare clip mod changes the color of parts of a weapon to a dull red.

Melee

 * Shotgun Melee Optimizer: Integrated VI improves synergy between melee weapon and firearm computer systems, allowing increased melee damage.
 * Shotgun Heavy Melee: Substantially increases melee damage, but at the cost of weapon weight.
 * Shotgun Light Melee: Substantially increases melee damage, but at the cost of clip size.

An equipped melee mod changes the silhouette of a weapon.

Receiver

 * Shotgun Receiver: Capacitor boosts kinetic coil generators, increasing shot penetration through solid objects.
 * Shotgun Calibrated Receiver: Allows shots to significantly penetrate solid objects, but reduces clip size.
 * Shotgun Quick Receiver: Allows shots to significantly penetrate solid objects, but reduces headshot/weak point damage.

The Venom cannot be equipped with a receiver.

An equipped receiver mod changes the color of parts of a weapon to a dull blue grey.