PC Case Montech AIR 903 BASE Midi Tower Black

The Montech AIR 903 BASE Midi Tower in black is a mid-tower PC case designed for airflow-focused builds. It comes pre-installed with three 140mm PWM fans (two front, one rear), a metal front panel with extensive ventilation, and support for multiple drive options including two 3.5" bays and five 2.5" bays. The case accommodates ATX and larger motherboards including E-ATX and SSI-EEB, provides space for long and wide graphics cards, and offers organized cable routing with a 27mm clearance, rubber grommets and Velcro straps.

Advantages

The AIR 903 BASE combines a high-ventilation metal front panel (approximately 51% open area) with pre-installed HP140 PWM fans to deliver strong airflow and effective cooling while maintaining low noise levels through adjustable fan speeds. Dust protection is simplified via strategically placed filters and a quick-release design for easier cleaning. The interior supports extensive cooling configurations—up to 360mm AIO radiators at the front and top and up to nine fans overall—while providing roomy clearance for large CPU coolers and GPUs up to 400mm long and 190mm wide. Cable management features and pre-punched mounting and routing holes streamline installation of ATX, E-ATX and SSI-EEB motherboards.

Suitable for

• Airflow-optimized gaming or workstation builds
• Systems using large GPUs (up to 400mm length, 190mm width)
• Configurations requiring multiple storage drives (2×3.5" and 5×2.5" support)
• Custom cooling setups with front/top 360mm AIO radiators or multiple fan layouts

Key specifications

• Type: PC case, Midi Tower
• Model: Montech AIR 903 BASE B (MPN AIR 903 BASE B, EAN 4710562743784)
• Pre-installed fans: 3 × 140mm PWM (2 front, 1 rear)
• Drive bays: 2 × 3.5", 5 × 2.5"
• Motherboard support: ATX, E-ATX, Micro ATX, Mini-ITX, SSI-EEB
• GPU support: up to 400mm length, up to 190mm width
• Radiator support: up to 360mm front/top
• Front ventilation: ~51% open area metal panel
• Exterior color: Black
• Dimensions (W×D×H): 230 × 478 × 493 mm
• Weight: 7.6 kg
• Front I/O: 2 × USB 3.2 Gen 1 Type-A

How to use

Install the motherboard using the pre-punched standoff holes and route power and data cables through the 27mm cable channel, using the rubber grommets and Velcro straps to secure cables and maintain a tidy interior. Fit storage drives in the designated 3.5" and 2.5" bays and mount the GPU in a standard or vertical orientation (vertical mounting kit sold separately) after removing the required PCIe slot covers. For optimal cooling, place radiators or additional fans in supported front or top positions and configure fan speeds via the motherboard or fan controller to balance noise and thermals.

Recommendations

Use the quick-release front panel and accessible dust filters for regular cleaning to maintain optimal airflow. When installing high-power graphics cards, ensure adequate clearance and consider front or top 360mm AIO cooling for lower component temperatures.