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Cooler Master MasterBox Q300L mATX Mini Tower Computer Case - Black

Cooler Master MasterBox Q300L mATX Mini Tower Computer Case - Black

  • I/O panel can be adjusted in 6 different locations and the Case can be positioned: vertical or horizontal
  • Edge-to-Edge Acrylic Transparent Side Panel offers a full view inside
  • Body depth height: can support normal size ATX power supply
  • Front Magnetic Design Dust Filter with open perforated front, top and bottom for high air performance
  • Extra space behind the motherboard tray for hidden cable management


Cooler Master Q 300L


The MasterBox Q300L is your straightforward option in the MasterBox Q-series from Cooler Master, a series that might be small in size but excels in functionality, modularity, and thermal performance.


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.


Patterned magnetic filters create a unique look for your chassis while keeping your system's internals free from excess dust.


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


Show off your build through the full size transparent side panel.


The open design of the perforated front, top, and bottom guarantees excellent thermal performance.


A space 28mm-wide behind the motherboard tray offers open space for hidden cable management.



Product NumberMCB-Q300L-KANN-S00
Available ColorBlack
MaterialsSteel, Plastic
Dimensions, L x W x H387 x 230 x 378mm
Motherboard SuportMicro-ATX, Mini-ITX
Expansion Slots4
Drive Bays5.25"0
3.5" HDD1
2.5" SSD2
I/O PortUSB 3.0 x 2, Audio In/Out
Pre-Installed Fan(s)Frontn/a
Rear120mm x1
Fan SupportFront120 / 140mm x2
Top120mm x2
Rear120mm x1
Bottom120mm x1
RGB ControllerIncluded
Radiator SupportFront120mm x1 / 240mm x1
Rear120mm x1
ClearancesCPU Cooler157mm
Cable RoutingBehind MB Tray28mm 
Dust FiltersBottom 
Power Supply SupportBottom Mount, ATX PS2 
EAN Code4719512065488 
UPC Code884102038006 
Net Weight3.7 kg 
Gross Weight4.7 kg 
Carton Dimensions, L x W x H435 x 276 x 461mm 


  • UPC


  • MPN


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