Trevor is part of the LSPD now, and they have been dispatched to stop a Vagos raid over the Chumash Plaza. For this shootout, Trevor received the HK416, a german assault rifle recently by the LSPD.

This weapon model consists on two parts:
-The base model: https://www.gta5-mods.com/weapons/girls-frontline-hk416-animated
-The Heckler & Koch skin: https://www.gta5-mods.com/weapons/heckler-koch-hk416