Sony a (alpha) DSLR-A100 Operating Instructions Manual page 21

Attaching the shoulder strap
This camera has two hooks to attach the
shoulder strap. Attach the end of the strap
with the remote commander clip on the grip
side of the camera. Attach the other end of
the strap on the other side of the camera.
Remote commander clip
Holder Ring
When threading the strap through the
holder ring, hold the tip of the strap with
your finger, as shown below, and slide the
holder ring rather than the tip of the strap
into position to secure the strap.
If the holder ring comes off the strap, put it
back on the strap from the notched side.
Notched side
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