Sorry for the late reply! Chain with Inside dimension 7x15 HxW and bending radius R15 was applied in-between the vertical gap 50mm of y-Base plate and x-axis unit brace plate . As only two wires (one is the x-axis motor shield wire Dia 5.2, the other is the limit switch wire D 4.0) are went through the chain, area capacity was no problem. But as the chain size was so small, it sometimes went off the route due it's small distortion~