The following view shows the rear of the carrier.
The card or filler panel is correctly seated when the notch at the top of the card bracket fits around a guide post on the carrier.
Note - If the I/O card includes a mounting screw, do not use the mounting screw. The carrier does not accept mounting screws.
The green latch should click into place.
If the top is difficult to close, verify that the notch of the card bracket or filler panel fits around the guide post.