this APEX2 cover was made to go with a special long range ladder sight. so you could use it with the “flatline mode” on your apex.
the idea was that since you have to place you Apex in a angle to make it shoot straight did I had the idea to place a grenade or long range sight on it so you can just flip the sights up and know that the rounds should fly out straight from this angle.
can you know this from experience sure. but some might like the look of it.
this sight was made to work with a Apex were there was no place on the Apex it self to place the sights on. so in case you like it to use this way as well then here is the rail option. or you might like it for some other reason.