DEC DECstation 5000 Model 100 Series Hardware Operator's Manual page 115

Push the cable connector all the way into the DESTA
9.
connector.
Use your finger or a simple tool, such as a flat-blade
10.
screwdriver, to slide the connector lock on the system unit.
Hold the ThinWire Ethernet T-connector and DESTA, as
11.
shown in Figure 6-5, on page 6-8. Notice that the collar on
the T-connector has two slots that fit over corresponding
pins on the DESTA connector.
Align the slots on the collar of the T-connector with the pins
on the DESTA connector, push the T-connector onto the
DESTA connector, and twist the T-connector to the right to
lock it.
Optional Network Connections 6–7