Out of the box, the Montech Air 900 ARGB looks eerily similar to the be quiet! Dark Base 700 in regards design. They say imitation is the sincerest form of flattery, and the inspiration for the Montech Air 900 results in a clean-looking chassis. The solid front has a nice texture to it, and its enclosed nature will make the chassis slightly quieter than the mesh variant.
Looking at the front, you can see the brushed look along with the company logo on the bottom half. It has two lines running along the sides, which, as the name of the enclosure suggests, are the embedded ARGB elements.
The main side panel is made out of glass that is held in place by four black thumb screws. Thanks to the light tint of the window, all your hardware will be clearly visible within the chassis. Unfortunately, Montech chose not to apply a black frame to the backside of the glass panel, so you can also clearly see the tooling holes of the frame. From a visual perspective, that addition would have made such a big difference in cleaning up the design. The side panel on the opposite side consists of a single, solid steel panel held in place with thumb screws.
You may pull off the front to reveal the three fan-mounting possibilities there. There is a magnetic dust filter you may easily remove for cleaning or changing your cooling setup. Montech includes a 120 mm intake fan with its own branding here, which, while without any frills, feels pretty sturdy and of good quality.
Looking at the rear, the bottom PSU bay comes with a single set of mounting holes. Above that are the eight expansion slots which come with break-out covers. While Montech has included two re-usable ones, I would have liked all of them to be of that kind. In the very top, you will find another 120 mm fan set to push hot air out the back of the Air 900 ARGB.
In the top, you will find a black metal mesh cover that is held in place magnetically as well. Underneath it are offset mounting holes for either two 120 mm or two 140 mm fans. With them so far away from the motherboard side, you are also able to opt for up to a 280 mm radiator here without issue. The I/O panel consists of two USB 2.0, two USB 3.0, and the usual audio connectors, along with the power and reset buttons. Montech also includes an LED toggle button, which isn't hooked up to anything but allows you to expand your case lighting with your own controller. Just looking at the design of this whole area, it is laid out identical to the be quiet! Dark Base 700 series.
On the underside, you will find another full-sized metal mesh cover that is also held in place with magnetic strips.