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Cooler Master

Cooler Master MasterBox Q300L Micro-ATX Tower with Magnetic Design Dust Filter, Transparent Acrylic Side Panel, Adjustable I/O & Fully Ventilated Airflow, Black (MCB-Q300L-KANN-S00)

    • Based on 12,431 reviews
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Availability: Only 2 left in stock, order soon!
Fulfilled by Amazon
Arrives Wednesday, Sep 18
Order within 4 hours and 40 minutes
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Color: Black


Style: Micro-ATX MB


Features

  • Magnetic Dust Filters: The unique pattern of the dust filter adds a distinctive appearance to the case.
  • 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
  • Ample Interior: Explore ample interior space for Micro-ATX or Mini-ITX motherboards, ensuring easy and future expansion

Description

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.

Brand: Cooler Master


Motherboard Compatability: Micro-ATX and Mini-ITX


Case Type: Mini-Tower


Recommended Uses For Product: Gaming


Color: Black


Material: Alloy Steel, Plastic


Power Supply Mounting Type: Bottom Mount


Cooling Method: Air


Model Name: Q300L


Item Weight: 480 Grams


Wireless Type: ‎802.11a


Brand: ‎Cooler Master


Series: ‎Q300L


Item model number: ‎MCB-Q300L-KANN-S00


Item Weight: ‎1.06 pounds


Product Dimensions: ‎15.39 x 9.06 x 15 inches


Item Dimensions LxWxH: ‎15.39 x 9.06 x 15 inches


Color: ‎Black


Department: ‎Computer Cases


Manufacturer: ‎Cooler Master


Country of Origin: ‎China


Is Discontinued By Manufacturer: ‎No


Date First Available: ‎December 5, 2017


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Sep 18

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Amazing Case For an Amazing Price! (Model: Q300L)
So first I'd like to state that this review is specifically for the Q300L model. Amazon does this annoying thing where they mix all the reviews of all the models together and I can't stand it so I'm just stating the model flat out. I just built my 10 year old nephew’s PC using this case and I have to say that I was very surprised at how much I loved building in this case. Originally I bought the Compucase HEC HX300 case for 30$ from Newegg and I was just frustrated at the lack of air flow from that case. It only had room for one fan which was the back exhaust and that's it. It didn't even have holes for the power supply's intake fan! It was my fault for not researching enough and buying something so cheap. Then I did a little research and came across this case. It is only 50$ but has everything I want. I've seen PC builders on youtube build with this case and they all had great things to say. So the first thing I like about this case is obviously how much airflow it allows. It's an interesting design because there are holes all over the top, all over the bottom, and all over the front and you can install 4 fans if you wanted to (2 up top, 2 in front, 2 in bottom) in addition to the included exhaust fan at the back making it support up to 5 fans! Now with all those holes you might be thinking this is going to be an ugly case but as you'll see in the pictures this is not the case (pun intended) and it has very sleek looking dust filters to cover the top, front, and it’s not obvious from the picture but it has a filter on the bottom as well. I was pleasantly surprised to see that the filter is magnetic which made removing them to install my fans a breeze (pun intended). I also imagine cleaning them when they get dirty will also be very simple. You can simple remove them and just rinse with water. One tip when installing fans is that since there’s air holes all over, they actually made a very small indentation around the holes that you should screw in your fans. These “guides” are hard to notice but if you look closely you’ll see them. They have space for 140mm and 120mm fans depending on whatever you want. Air is able to easily flow through the filter so my air flow issues were resolved! The case also looks very nice in my opinion. I have the black model just because that’s what my nephew wanted but in review videos I’ve seen, the white one looks very nice as well. Cable management at the back is pretty good too and the case comes with a lot of zip ties. The filters I mention above are also very aesthetically pleasing. The power button, 2 USB ports, headphone jack, and speaker jack are on the side which I don’t mind. The interesting thing is that this IO panel can be unscrewed and moved to the other side which is nice. The clear side panel is acrylic but it’s a 50$ case so it’s fine. It doesn’t look bad at all. There’s also room in the cable management area for a 3.5” hard drive and 2 SSD’s inside the main area which is very good. Overall the case was pretty simple to build in. It’s designed very well to maximize airflow while looking great. I think this is an excellent case especially for the price. If you’re in the market for a cheap but good PC case, then you my friends have stumbled on a cheap but GREAT PC case. I would highly recommend this case and am willing to do even more expensive builds with this case in the future. One final note I’ll add, I built my nephew’s pc with a Ryzen 5 1600 processor and RX 480 gpu reference model targeting 1080p gaming and the heat in my old case with that one exhaust fan was reaching around 87 degrees C. After I added two intake fans in the front and one exhaust fan in the top along with the back exhaust fan that comes with this case my temperatures went down into the mid 70’s while gaming which is great. If you want looks as well as functionality for a great price, go with this case. ... show more
Reviewed in the United States on June 25, 2020 by Fa
    • Great box, I wound up buying 6 and replaced some old ones I had as well
shipping was a bit of a gamble, some came fast others not so much. The box is a good size, extremely well designed with ventilation on all sides, top and bottom. Will buy more as needed. Price is very reasonable
Reviewed in the United States on June 1, 2024 by Robert J Medlin
    • Takes some work
Look, let's jump to the point: this thing is difficult to build in. If you are putting together a desktop with larger components or more storage, I would look at something else. However, it's a very economical case with *acceptable* cable management, and if you are building something like a NAS, HTPC, server, or any PC really with a low-profile cooler or AIO, it will go together in less than an hour, especially if you don't care about what you see through the window. Here's what I managed to stuff in it in a much longer timeframe: -i5-whocares-it's-from-2019 -asrock mini-itx motherboard -Noctua NH-U12a tower cooler -geforce rtx 4060 -2x sata SSD's -4x 120mm case fans (one of the two available CPU cooler fans) -sleeved PSU cable extensions Pros: - compact, pretty standard construction: riveted together, metal and plastic side panels - you can move the IO panel around - pretty flexible fan placement with 120mm fans - pretty flexible SSD mounting, even more if you're willing to use mounting tape - nice dust filter config and great airflow, although they do move around a lot handling the case Cons: - very little space between top of motherboard and top of case. Mounting a radiator up top would require splitting the radiator and fans both inside and outside of the case. Putting an exhaust fan above a tower cooler would be impossible as well without putting it outside the case - because of this space, it's also difficult to connect an 8-pin CPU connector at the top of the motherboard. If you have a modular PSU or extension cables, connecting the cable before installing the motherboard is essential but also cover the mounting hole on my motherboard - rear exhaust fan mount not "countersunk", it will be very close to whatever cooler you use, which is why I could only use one CPU cooler fan - cable management space is pretty thin - one HDD mount which cuts down even more on cable management space if you actually put anything on it. Overall it's a good case for what it's designed for, and v2 is supposedly better. ... show more
Reviewed in the United States on May 18, 2024 by Amazon Customer

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