Additional ventilation on the opposite side allows for a 120mm fan (not included) to be mounted on the side of the case for added air flow. The side panels are overall easy to remove/install, however the back panel can be challenging if trying to attach too much cabling behind the motherboard tray. The panels are made out of lower gauge steel, and as a result they can flex slightly when applying force to close the case. The side panels are secured closed at the back of the case with the use of two thumb screws each.
The inside of the case offers plenty of space to install a full size ATX board, not to mention the beautiful power coated black gives is a clean look. Micro-ATX and mini-ITX are also supported. As with many of Antec’s current designs, the One has a floor mounted power supply. The benefit of this is that hot air from the case isn’t exhaust via the power supply (thus making the power supply extra hot), as with cases having top mounted units.
The One comes with two 120mm fans pre-installed: one on the top and one on the rear. They are both oriented as exhaust fans, and are powered via 3-pin connectors. There is also a fan mount at the bottom of the case that accepts 120 & 140mm fans. Typically, bottom mounts for fans are used for air intake, but it should be noted that there isn’t a dust filter for this vent. This would make it a poor choice for air intake as a result.