|Flechette Ammo||$50,000||Less Damage, more precise|
|12 Gauge Slugs||$75,000||
Most damage, more recoil
4 extra rounds chambered, higher rate-of-fire
|Butt Stock||$50,000||Less recoil, more precision|
|Silencer Type 1||$200,000||
Less noise, less damage
More damage, less precision
|Red dot sight||$200,000||Most zoom, more precision (requires rail mount)|
|Reload boost (Speedloader)||$50,000||
|Laser sight||$150,000||More precision|
|Extra Ammo||$75,000||2 extra rounds, larger chamber/magazine capacity|
|Rail mount||$75,000||Required for red dot sight|
- While equipped with magazine, the reload will be exchange the magazine instead of load using the pump-action.
- Use the magazine upgrade is still fire using pump-action, though Agent 47 will fire faster, but it really boosts the reloading speed, especially if you empty the weapon before reloading.
- This weapon can fire semi-automatically, however this feature is not seen in the game.
- Even if you are empty, the shells on the speedloader will still be visible.
- Using the silencer will still be noticed by nearby NPCs on higher difficulties.
- When equipped the slugs, you will have a little more kill range, due to its tight pellet spread, by contrast, the flechette round require you to close up to deal lethal damage to your target. The latter ammo type has a higher hit ratio due to its wider spread pattern.
- The Red dot sight is entirely optional, since the SP12 is close range weapon. If you want to hit your foe quickly with precision, Laser sight will be a better choice.
- In real life, the stock on the Spas-12 is the standard attachment, it can be folded if not needed.