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CoolerMaster MasterBox Q300L Micro-ATX Case - Black Window
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CoolerMaster MasterBox Q300L Micro-ATX Case - Black Window

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Product Description

CoolerMaster MasterBox Q300L Micro-ATX Case - Black Window

The MasterBox Q300L is your straightforward option in the lineup of the brand new MasterBox Q-series from Cooler Master. A series that might be small in size but excels in functionality and modularity without compromising on the thermal performance.

Although the size wouldn’t tell, the MasterBox Q300L supports a standard ATX PSU which we don’t see often in the market with this size. Based on the different system setup, the I/O panel can be adjusted to six different locations, three options at each side of the case. You can decide which setup fits your system best.

Due to the cube design of the frame and special pattern design on the magnetic dust filter will make the chassis stand out from the rest. The combination of a practical design and the unique customizable outlook makes the MasterBox Q300L the perfect choice for office and home usage.


- High Flexibility for System Building: The I/O panel can be adjusted to six different locations. On both side of the body you can install the I/O panel at the front, top or bottom.

- Minimized Dimension with ATX PSU Support: Despite the Micro-ATX form factor and the body depth and height of only 370mm x 370mm, the MasterBox Q300L can accommodate a normal ATX PSU.

- Patterned Dust Filter: Special pattern on the dust filter creates a unique outlook for the chassis.

- Clean Routing Space: Behind the motherboard tray, it offers 28mm wide and spacy room for hidden cable management.

- Excellent Thermal Performance: The open design of the perforated front, top and bottom guarantees excellent thermal performance.

- Edge-to-Edge Acrylic Transparent Side Panel: Show off your build through the full size transparent side panel.

- Vertical and Horizontal position: The case can be put in vertical and horizontal position.


- Product Name: MasterBox Q300L

- Product Number: MCB-Q300L-KANN-S00

- Available Colour: Black

- Materials: Steel, Plastic

- Dimensions (LxWxH): 387 x 230 x 378mm

- Motherboard Support: Micro-ATX, Mini-ITX

- Expansion Slots: 4

- Drive Bays: 5.25" - 0, 3.5" HDD - 1, 2.5" SSD - 2

- I/O Port: USB 3.0 x 2, Audio In / Out

- Pre-installed Fan(s): Front - N/A, Rear - 120mm x 1

- Fan Support: Front - 120 / 140mm x 2, Top - 120mm x 2, Rear - 120mm x 1, Bottom - 120mm x 1

- Radiator Support: Front: 120mm x 1 / 240mm x 1, Rear - 120mm x 1

- Clearances: CPU Cooler - 157mm, PSU - 160mm, GPU - 360mm

- Cable Routing: Behind MB Tray - 28mm

- Power Supply Support: Bottom mount, ATX PS2

Case typeMidi-Tower

Form FactorMicro-ATX, Mini-ITX

Side panelTempered glass


Main colourBlack

Noise dampeningNo

Width (exact)230mm

Height (exact)450mm

Depth (exact)450mm


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CoolerMaster MasterBox Q300L Micro-ATX Case - Black Window
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