The Classic Army Blowback Linkage is a small metal part that is critical to the proper function of the Classic Army blowback AEGs. The link arm connects the piston to the fake bolt, driving the electric blowback. If this arm breaks, the blowback will be non functional.
The CA ABS, or Auto Blowback System, is found in the blowback M15A4 series, as well as the Tango Down ECR AEGs and the LWRC M6 AEGs. This part is compatible with all series of CA EBB rifles.