Acer Altos G5450 Series - Manual (Page 140)

Appendix B: Rack mount configuration 122
3 Remove the inner rails from the mounting rails.
(1) Extend the inner rail from the mounting rail until the rail
release latch is exposed.
(2) Depress the release latch (1) and slip the inner rail out (2).
Do the same thing to the other mounting rail.
4 Attach the rack handles and inner rails to the server.
(1) Align the screw holes on the rack handles with those on the
server.
(2) Secure the rack handles with two U#6-32 x 6.4 screws each.
(3) Insert the pegs on the server with the notches on the
mounting rails, then slide the mounting rails backward to seat
them properly.
(4) Secure the mounting rails to the server with two M4 x 5 screws
each.