Price: $39.99
(as of Oct 14, 2025 18:45:04 UTC – Details)
The Master Box Q300L is your straightforward option in the lineup of the brand new Master Box 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 Master Box 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 Master Box Q300L The perfect choice for office and home.
Ample Interior: Explore ample interior space for Micro-ATX or Mini-ITX motherboards, ensuring easy and future expansion
Components Clearance: Accommodates CPU coolers with a max height of 159mm, GPU cards up to 360mm, and PSU up to 160mm in length.
Versatile Cooling: Maximize cooling performance with a 240mm liquid cooler and 5 fans.
Modular I/O Panel: You have the flexibility to adjust its position at the front, top, or bottom on both sides
Edge-To-Edge Panel: Show off your meticulous build through the transparent side panel with pride.
Open Thermal Design: The perforated design on all sides promotes optimal airflow and heat dissipation
Magnetic Dust Filters: The unique pattern of the dust filter adds a distinctive appearance to the case.
Customers say
Customers find this case to be a great budget option with sturdy metal construction and ample space for cable management. They appreciate its professional appearance, with one customer noting it fits well in an office setting. The airflow and cable management receive mixed reviews – while some praise the ventilation, others find it lacking, and while some find cable management easy, others report it’s a nightmare.