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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)

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$39.99

$ 19 .99 $19.99

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1.Style:Q300l


About this item

  • 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


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.


Houston
Reviewed in Canada on February 17, 2025
Good sturdy box. Holds all my parts with space for extra fans. Would recommend to others.
Jesus Holz
Reviewed in Mexico on February 13, 2025
Llegó antes de tiempo y en perfecto estado, es tal cual se describe, no tiene ningún daño se ve espectacular! , apenas haga mi ensable actualizaré las imágenes
Trevor
Reviewed in the United States on January 17, 2025
Cost friendly, light weight, excellent airflow, fits everything great. The mesh style walls makes it easy to place fans however you would like. Liquid coolers fit perfectly. Wire management is great with these cases. Super easy to feed wires, easy to disassemble and reassemble. I’ve built 10+ computers as budget friendly builds for people in my area using these and could not be more satisfied. 10/10 recommend!
RinSant
Reviewed in Mexico on November 30, 2024
Sin duda valió la pena cada peso, es un gabinete hermoso, elegante, y tiene todo lo necesario bien pensado, me encantó y llegó muy rápido a la ciudad de México, 10/10
Atomic Penguin
Reviewed in the United States on November 21, 2024
An interesting little "small form factor" case. Key word here is "small". Seems to be relatively well made. Option to move the position of the front panel is clever, BUT you have to be sure everything will fit. I moved my front panel to the top edge of the case (see photo) , but then had to "void my warranty" with a Dremel tool to get a Cooler Master HYPER 212 Halo air cooler to fit (it looks great).Plenty of room in back for cable management, plenty of room for a PSU. BE CAREFUL about the length of your GPU. Plenty of room for two 140mm fans in front. Had to use 120's on top and in back. VERY little clearance between motherboard and frame of the two Cooler Master MF120(2) fans on top. The motherboard is actually touching the frame of the fans (!). But everything works fine.Also, very difficult (impossible?) to connect the 'upper' power cables to motherboard while in place. I routed the cables through the corner of the case, connected them, and THEN installed the motherboard.The case has "El Cheapo" break-out PCIE slot covers - but remember that this is a VERY inexpensive case.The overall case is quite aesthetic and well thought out. Just remember that there is not much room in the case, so the build may be challenging.
Philippe
Reviewed in Canada on April 20, 2023
Purchased this case for a budget Micro-ATX build. The case is very well built. Lots of value for your money here. It comes with everything you need, an exhaust fan, screws and even a bag of zip ties! Cable management was a breeze, plenty of space and holes to route wires through. I like the magnetic meshdust covers. Plenty of airflow on this case, my components stay cool and run smooth. Only slight little downside is the way the power supply is mounted with a bracket instead of flush against the back. Not a deal breaker but on my power supply, it slightly blocks the direct path for the power cable / socket. It still works albeit "forced" in. Overall though, I would highly recommend. Excellent quality and offering for the price.
Customer
Reviewed in Mexico on August 28, 2021
Este gabinete lo voy a utilizar para una computadora no tan potente, pero lo probé con mi computadora principal que utiliza un Ryzen 7, y una Vega 64 que es bastante demandante en cuanto a enfriamiento y no me dio ningún problema, la calidad de construcción es bastante sólida, tiene un excelente flujo de aire, mucho mejor que mi gabinete Thermaltake principal, e incluye los filtros de polvo en 3 de las 4 entradas de aire posibles que reducen la necesidad de limpieza, Es un gabinete muy compacto y flexible, sin embargo tiene 2 desventajas, 1, no permite montar un radiador de 240mm como exhaust arriba de la tarjeta madre, solo al frente, y la ventana es de acrílico, el radiador se puede ignorar, solo es una cuestión de preferencia personal, pero me encantaría ver una ventana de vidrio templado si lo fuera a usar como mi gabinete principal, no me molestaría pagar un poco más por esa opción, si buscas un gabinete Micro ATX con vidrio templado a buen precio yo me inclinaría por el Thermaltake S100 aunque el flujo de aire no es tan bueno y solo tiene 2 filtros de polvo.
Fa
Reviewed in the United States on June 25, 2020
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.
Bubba Grimm
Reviewed in the United States on May 28, 2019
When I was picking my parts, I wanted to spend as little as possible on a case without going into the ultra budget rosewills and what not. Pretty much every case I was interested in was either in the $60 range or the $100+ range. I was going to settle on the thermaltake v21 and replace all the sides with windows, then I was going to settle on the fancy version of the q300l.I kept researching and researching and it sounds like cooler master fans aren't that great so getting two rgb ones with the fancy version sounded like a good deal but I had found plenty of cheap 6 packs of rgb fans and would prefer if all matched. This case at below $40 was just simply the most unique one at this price range and I had already decided on all the other parts (don't pick the case first) and tried imagining the build.I changed my mind on getting ring style fans, the perforated nature of this case would completely ruin the rings' lighting thru the walls, so the other option was fully lighted fans. Definitely the right choice in this one. You need to be careful with CPU coolers too, several popular ones are too tall by less than a mm. Just happens that the fans I got, uphere's (I took a chance and they are so good, don't let the brand scare you) also come on uphere's cooler and it fits PERFECT. No touching the side panel or anything. I didn't realize how black the case was as well and that is such a good thing. It is black, not grey.Cable management was as easy as can be with zip ties and fabric ties. Plenty of space to feed any cable heads thru any open route, I never got frustrated or had a problem making it look how I wanted.There's mixed info on the cooling performance. Lots of holes=lots of air. Gamers Nexus proved that false but I have yet to see temps over 75c during all benchmarks. Probably due to 9 fans.It just looks clean. I don't know if you can tell from the pictures.Cons: it's a cheap case so it's got more of a bare bones metal look than a sleek spaceship look. Not necessarily a bad thing.I really can't think of anything else, it was a complete joy to build in and everyone who's seen it really appreciates it. Would definitely recommend for budget builds and high end ones and is a perfect choice for custom builds built in quantity for offices and such at such a cheap price.Don't hesitate, if you think this case looks good even a little bit, it looks better in person and you shouldn't be disappointed.Make sure you are using micro atx motherboard. Just saying. Some people. Normal atx psu fits with a recessed bracket, thought it was weird but now I actually like it. It allows the power cable to bend at the edge of the case as opposed to sticking out and inch or so.Definitely a buy for those on a budget.
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