Tool / Crafting Material Max Carried: 1
A rail that can be fixed to your shotgun, allowing for attachments on the weapon.
How to Find the Shotgun Rail
The shotgun rail can be found in six different places, which is a lot when considering you can only find the shotgun in two places. The easiest location to get to is right next to where you originally find the shotgun (1). Just head north of the grave with the shotgun, and you’ll find an abandoned camp. The shotgun rail will be in a case by a tent (2).
Here’s a list of the other locations with the shotgun rail, in case you’re closer to those:
In the food bunker, in the same room where you find the VIP keycard.
In the bunker where you get the guest keycard, behind the locked door in the nightclub (use guest keycard to open door).
In the residential bunker on the 2nd floor in a closet with purses, next to slug ammo.
On the northwestern beach at the camp where you find the machete, will be on corpse by tent.
In the far eastern bunker (endgame bunker), on the kitchen counter with slug ammo.
How to Use the Shotgun Rail
The shotgun rail can put on the shotgun in the inventory menu. Go up to the black case and hover over the shotgun and press the button labeled “combine”, then do the same for the shotgun rail. This places them on the crafting mat, then select the gear in the top-right of the mat to put the rail on the firearm. Even though there are places on the rail for shotgun shells, this does not affect the reload speed.
Now that the rail is on the shotgun, you can attach two paraphernalia to the weapon: