Mke ap5-p (mp5-k clone) may require fitment/modification. - FAB Defense Heckler & Koch MP5K Aluminum Picatinny Rail System

Works great! After removing the sling loop, filling it close to the sight tower it was a very tight fit. I also had a small hang up on the bottom of the reciver but weld, after removing a very small amount from it, because the chucking tube hanger wasnt lining up, the rear of the handgaurd was able to clamp the reciver/trunnion. The 3 lug portion of the barrel is covered halfway, ID of the end of handgaurd is about 1 3/8". Total over length of the handgaurd is 4 1/4" , length from front of the trunnion to rear of the handgaurd is 9/16", length from front of trunnion to end of the handgaurd is 3 11/16".