Quick look at the ICS Airsoft CXP-HOG Tubular SD MTR AEG available at Gunfire... "A top-shelf replica of a manufacturer known for its high-quality workmanship. ICS CXP-HOG Tubular SD MTR is a combination of aluminum, steel, and composite activities in perfect proportions. The upper part of the aluminum body is made of one piece with the use of CNC machines. The heart of the ASG replica is a two-part 'ICS Split Gearbox' with a quick spring change system."