Advantech ADAM-6520 Series - Figure 2.5:DIN-Rail Mounting; Figure 2.6:Piggyback Stacking

ADAM-6520 User Manual 12
DIN-rail Mounting
You can mount ADAM-6520 modules on a standard 35 mm DIN-rail.
First, use two screws to attach the DIN-rail bracket to the ADAM-6520
modules. Because ADAM-6520 modules use special hex head slotted
shoulder screws, the tops of the screws will be even with the front of the
module. Snap the module onto the DIN-rail.
Figure 2.5: DIN-rail Mounting
Piggyback Stack
Several ADAM-6520 modules can be stacked as seen in the figure below
Figure 2.6: Piggyback Stacking