Check Point 21000 Series Installing And Removing Memory page 10

Only touch the top corners of the DIMM. Pressing on the heat sink or
other DIMM components can damage the hardware.
The top of the DIMM is smooth. The bottom edge has two
different-length sets of contacts, which connect to the slots on the
socket.
WARNING! - There are sharp metal parts in the appliance, like the heat
sink fin and bracket, that can cause injury and damage the hardware.
4. Press the new DIMM into the socket until it clicks into position.
The retaining clips move into the lock position as you press the DIMM
into position.
5. Do steps 1 - 4 again for the other memory DIMMs.
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