Asus AP1720-E2 - Manual (Page 46)

Chapter 2: Hardware setup 2-26
2.8 Expansion cards
The chassis is designed with a screwless expansion slot frame on the rear
panel. This design feature allows you to install or remove an expansion
card in less steps.
Make sure to unplug the power cord before installing or removing
expansion cards. Failure to do so may cause physical injury, and
damage to the card and motheboard components!
2.8.1 Installing a standard size expansion card
To install a standard size expansion card:
1. Remove the plastic card lock opposite the slot where you wish to install
the expansion card. Release the card lock by pressing the center tabs
and pushing outward. Set the card lock aside for later use.
2. Carefully install an expansion
card making sure that it is
properly seated on the slot.
Card lock tab