This is a red dot sight to pair with my other model of pistol granade launcher but it can be put in other helldiver temed models if they had a picatinny rail in them , is a bit wiggly with picatinny of that model but since them i have estandarice the tolerances of the rail system , for assembling it one has to glue the two parts together and then put it in the picatinny and screw it , it uses an attachment that i design myself and it should be easy to take out .