HP J2600A Installation Manual page 23

Installation
3. Install the Router Module.
6. Position the SNMP module, component-side down, above the router
module as shown below.
Before mating the modules, make sure that the four standoffs
mounted on the router module are aligned with the inner of the two
holes in each corner of the SNMP module. This is the hole closest to
the center of the module, not the hole closest to the corner.
Figure 1-6. Positioning SNMP Module Over Router Module
7. Lower the router module onto the SNMP module, then carefully
press down on the circuit side of the SNMP module, alongside the
connector mounting pins, until the SNMP module is flush with the
tops of the standoffs.
Press here
Figure 1-7. Engaging Module Connectors
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