AR-15s
Weaver and picatinny are the rails that you would mount stuff to, generally on top of a rifle or sometimes under the barrel on a pistol. They are the sideways rectangles that you see on some. The picatinny has wider grooves between the block as you can see in the pic. The grooves are where the attaching screws go through.
For MLOCK, it's an oval cutout in a handguard that is also used to attach things. The screw goes into the oval and there is a plate or a T nut that goes inside to clamp down to, if that makes sense. There is also Keymod, which is the predecessor to MLOCK, effectively doing the same thing in a similar nature. Here's a pic of those. In the pic, the top of those handguards also have a picatinny rail. The MLOK and KEYMOD are on the sides.
As for that sight, I haven't heard of the brand, so I can't comment. But a holographic sight projects the red dot out in front of you to appear to be on the target, as seen in this pic.
Weaver and picatinny are the rails that you would mount stuff to, generally on top of a rifle or sometimes under the barrel on a pistol. They are the sideways rectangles that you see on some. The picatinny has wider grooves between the block as you can see in the pic. The grooves are where the attaching screws go through.
For MLOCK, it's an oval cutout in a handguard that is also used to attach things. The screw goes into the oval and there is a plate or a T nut that goes inside to clamp down to, if that makes sense. There is also Keymod, which is the predecessor to MLOCK, effectively doing the same thing in a similar nature. Here's a pic of those. In the pic, the top of those handguards also have a picatinny rail. The MLOK and KEYMOD are on the sides.
As for that sight, I haven't heard of the brand, so I can't comment. But a holographic sight projects the red dot out in front of you to appear to be on the target, as seen in this pic.