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expiredPennyFound | Staff posted May 14, 2026 06:41 AM
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expiredPennyFound | Staff posted May 14, 2026 06:41 AM

Cooler Master MasterBox Q300L microATX Tower PC Case w/ Magnetic Dust Filter

+ Free S&H

$35

$45

22% off
Amazon
21 Comments
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Deal Details
Amazon has Cooler Master MasterBox Q300L microATX Tower Computer Case with Magnetic Design Dust Filter (MCB-Q300L-KANN-S00) on sale for $39.99 - $5 when you 'clip' the coupon on the product page = $34.99. Shipping is free.

Thanks to Deal Hunter PennyFound for sharing this deal.

Note: You must be logged in to clip coupons; coupons are typically for one-time use.

Product Details:
  • 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.

Editor's Notes

Written by Nate650 | Staff
  • About this deal:
    • Our research indicates that this deal is $5 less (12.5% savings) than the next best available price from a reputable merchant with prices starting from $39.99 at the time of this post.
  • About this product:
  • About this store:

Original Post

Written by PennyFound | Staff
Community Notes
About the Poster
Deal Details
Community Notes
About the Poster
Amazon has Cooler Master MasterBox Q300L microATX Tower Computer Case with Magnetic Design Dust Filter (MCB-Q300L-KANN-S00) on sale for $39.99 - $5 when you 'clip' the coupon on the product page = $34.99. Shipping is free.

Thanks to Deal Hunter PennyFound for sharing this deal.

Note: You must be logged in to clip coupons; coupons are typically for one-time use.

Product Details:
  • 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.

Editor's Notes

Written by Nate650 | Staff
  • About this deal:
    • Our research indicates that this deal is $5 less (12.5% savings) than the next best available price from a reputable merchant with prices starting from $39.99 at the time of this post.
  • About this product:
  • About this store:

Original Post

Written by PennyFound | Staff

Community Voting

Deal Score
+43
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Price Intelligence

Model: 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)

Deal History 

Sale Price
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Current Prices

Sort: Lowest to Highest | Last Updated 6/13/2026, 04:15 AM
Sold By Sale Price
Amazon$39

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Top Comments

GrandmasterBBC
2336 Posts
313 Reputation
If you are on a strict budget then this case certainly gets the job done. However, I despise the acrylic side panel. Those things get scratched up just by looking at them. I wish Cooler Master could offer the v2 version with tempered side panel glass for less than $62.

21 Comments

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May 14, 2026 04:58 PM
2,336 Posts
Joined Nov 2011
GrandmasterBBCMay 14, 2026 04:58 PM
2,336 Posts

Our community has rated this post as helpful. If you agree, why not thank GrandmasterBBC

If you are on a strict budget then this case certainly gets the job done. However, I despise the acrylic side panel. Those things get scratched up just by looking at them. I wish Cooler Master could offer the v2 version with tempered side panel glass for less than $62.
1
2
May 14, 2026 05:47 PM
12,649 Posts
Joined Nov 2010
PeteyTheStrikerMay 14, 2026 05:47 PM
12,649 Posts
I have the Asus TUFF version of this case. Have been using it for about 5 years now. Overall a great case with many options and space for install. Only thing that is annoying is that if you have a large graphics card RTX 3080 or above and you use front mounts for cooling AIO space will become very tight. In most cases installing and uninstalling the graphics card for maintenance and cleaning becomes a pain cause its just a tight fit. Besides that, I paid double this price and have been overall happy with the case.
2
May 14, 2026 08:12 PM
188 Posts
Joined Dec 2005
punkdigeratiMay 14, 2026 08:12 PM
188 Posts

Our community has rated this post as helpful. If you agree, why not thank punkdigerati

I would consider the cost of adding enough fans to get decent airflow, the holes in the case plus the filters add a lot of static resistance so you need fans that could work for a radiator. It may end up cheaper getting a different case.
The plus with the case holes is that you can position the fans in many more configurations than they mark, which can make a huge difference because this is a truly tiny case, the order you install things will make a difference in the ability to plug stuff into the motherboard.
3
May 14, 2026 09:15 PM
34 Posts
Joined May 2020
CrimsonRiver637May 14, 2026 09:15 PM
34 Posts
I need RAM to come down before I do anything!
1
May 14, 2026 11:45 PM
232 Posts
Joined Jul 2023
PanicAtTheCostcoMay 14, 2026 11:45 PM
232 Posts
they're still trying to peddle this garbage 5 years after GamersNexus slammed it as their worst case ever made?

lol
1
May 15, 2026 12:29 AM
91 Posts
Joined Dec 2025
MisterTranceMay 15, 2026 12:29 AM
91 Posts
Looks a bit awkward to me.
1
May 15, 2026 01:05 AM
44 Posts
Joined Apr 2009
immutablemanMay 15, 2026 01:05 AM
44 Posts
Quote from PanicAtTheCostco :
they're still trying to peddle this garbage 5 years after GamersNexus slammed it as their worst case ever made?

lol
i thought they slammed the ATX version. this is the littler brother mATX where the power supply is below not blocking the front. but IF they did slam this one, i'd like to know because i was thinking about it. you're also totally right that it has the same dumb frame air flow holes though.

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May 15, 2026 02:51 AM
9,463 Posts
Joined Oct 2008
DontTaxBeerMay 15, 2026 02:51 AM
9,463 Posts
Quote from PanicAtTheCostco :
they're still trying to peddle this garbage 5 years after GamersNexus slammed it as their worst case ever made?

lol
no drive bays. basically the drives are put in the back of the board with zero airflow. they wont last long.
May 15, 2026 02:55 AM
1,579 Posts
Joined May 2011
nathan646May 15, 2026 02:55 AM
1,579 Posts
Quote from PanicAtTheCostco :
they're still trying to peddle this garbage 5 years after GamersNexus slammed it as their worst case ever made?lol
Isn't this case super old? I swear I remember looking at this while building my Athlon64 3200+.
May 15, 2026 12:23 PM
72 Posts
Joined Mar 2018
draiggoch83May 15, 2026 12:23 PM
72 Posts
This is the worst case I've ever built in. Sure it will get the job done, but there are far better cases that go on sale for similar prices. The ventilation is awful and the acrylic side panel is extremely cheap looking and scratch prone.
May 15, 2026 12:28 PM
122 Posts
Joined Nov 2013
sqlman56May 15, 2026 12:28 PM
122 Posts
I had and liked this case the 3 days I had it until I realized I bought a full atx bundle and no way was it gonna fit. The magnetic dust filters were what set it apart. Other brands and cases have that but at this price point it's hard to beat
May 15, 2026 02:34 PM
994 Posts
Joined Dec 2015
ian-YoungMay 15, 2026 02:34 PM
994 Posts
Good case for its price. I have the same one, bought it several years back. My son now using it
May 15, 2026 04:20 PM
68 Posts
Joined Jun 2018
LumberjackJackMay 15, 2026 04:20 PM
68 Posts
I'm still having my first cup of coffee so maybe I'm missing something, but according to the Deal History isn't this a price spike not a price drop? The graph shows it as being cheaper than this for the past few months... what am I missing?
May 15, 2026 04:24 PM
68 Posts
Joined Jun 2018
LumberjackJackMay 15, 2026 04:24 PM
68 Posts
IMHO, the QUBE 540 is going to be the case we will be wishing we'd bought more of in the future, and it is cheaper now than it has ever been. If it ever truly goes on sale I plan to buy several.

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May 15, 2026 04:27 PM
68 Posts
Joined Jun 2018
LumberjackJackMay 15, 2026 04:27 PM
68 Posts
Speaking of cases, does anyone else lament not stocking up on the old "LAN Party" cases like the CM Scout back in the day? That kind of case marked the end of an era... they will never come back.

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