# PC case Cooler Master MasterBox Q300L Midi Tower Black

**URL:** https://aio.lv/en/product--cooler-master-mcb-q300l-kann-s00--562027
**Data updated:** 2025-12-28 21:28 (EET)
**Category:** Computer Cases
**Manufacturer:** Cooler Master
**Manufacturer code:** MCB-Q300L-KANN-S00
**EAN:** 4719512065488
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 46.49 €
**Prices and availability valid until:** 2026-07-27 23:59
**Price without VAT (21%):** 38.42 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--cooler-master-mcb-q300l-kann-s00--562027

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 13.07.2026 | free |
| Pickup points | 16.07.2026 | 1.89 EUR |
| Courier delivery to door | 16.07.2026 | 4.99 EUR |

## Summary description

The Cooler Master MasterBox Q300L is a Midi Tower PC case designed for optimal airflow and cooling. It features a bottom-mounted power supply, supports ATX and PS2 power supply form factors, and accommodates front fans with diameters of 120 and 140 mm. The case comes with one pre-installed 120 mm rear fan and supports HDD sizes of 2.5" and 3.5". With dimensions of 230 mm width, 387 mm depth, and 378 mm height, it offers a compact yet spacious design for your components.

## Long description

The Cooler Master MasterBox Q300L is a compact Midi Tower PC case designed to combine modular layout and effective airflow in a small footprint. Its cube-inspired frame includes a removable magnetic dust filter with a distinctive pattern and an adjustable I/O panel that can be positioned in six locations to match different system orientations. Despite the compact size, the case supports a standard ATX power supply and is supplied with one 120 mm rear fan, offering practical compatibility for office or home builds.
Advantages
The MasterBox Q300L provides flexible I/O placement, support for an ATX PSU in a compact chassis, and a ventilated design with a pre-installed 120 mm rear fan to improve cooling. The magnetic dust filter with a special pattern is easy to remove and clean, and the chassis accepts both 2.5" and 3.5" drives while maintaining a small external footprint.
Suitable for
Compact home or office PC builds
Micro ATX or Mini-ITX motherboards
Systems requiring a standard ATX power supply in a small case
Setups prioritizing easy maintenance and airflow
Key specifications
Type: PC case, Midi Tower
Supported motherboard form factors: Micro ATX, Mini-ITX
Dimensions (W×D×H): 230 × 387 × 378 mm
Weight: 3.7 kg
Drive bays: 1 × 3.5", 2 × 2.5"
Pre-installed fans: 1 × 120 mm (rear)
Front fan support: 120 mm, 140 mm
Power supply: supports standard ATX PSUs (bottom-mounted); PSU not included
Front I/O: 2 × USB 3.2 Gen 1 Type-A
Side window: Yes
Material: Steel, Plastic
Colour: Black
How to use
Install a Micro ATX or Mini-ITX motherboard and route cables to the rear and bottom channels to maintain airflow. Fit the ATX power supply in the bottom compartment and secure 3.5" and 2.5" drives in the provided bays. Place additional 120 mm or 140 mm fans in supported front positions if extra intake is needed. Adjust the I/O panel to one of the six available positions to suit your desk or case orientation, and attach the magnetic dust filters as required.
Usage recommendations
For best thermal performance, use at least one front intake fan (120 mm or 140 mm) paired with the included 120 mm rear exhaust. Regularly clean the magnetic dust filter to maintain airflow and ensure components remain dust-free.

## Specifications

### Design

| Feature | Value |
|---|---|
| Type | PC |
| Form factor | Midi Tower |
| Supported motherboard form factors | Micro ATX, Mini-ITX |
| Number of 3.5" bays | 1 |
| Number of 2.5" bays | 2 |
| Side window | Yes |
| Material | Steel, Plastic |
| Product colour | Black |
| Anti-dust filter | Yes |
| Maximum CPU cooler height | 157 mm |
| Maximum graphics card length | 360 mm |
| Number of expansion slots | 4 |
| Maximum PSU length | 160 mm |
| LED indicators | Y |
| Cable management | Yes |

### Power supply

| Feature | Value |
|---|---|
| Power supply included | No |
| Power supply location | Bottom |
| Supported power supply form factors | ATX, PS2 |

### Ports & interfaces

| Feature | Value |
|---|---|
| USB 3.2 Gen 1 (3.1 Gen 1) Type-A ports quantity | 2 |
| Audio input | Yes |
| Audio output | Yes |

### Cooling

| Feature | Value |
|---|---|
| Cooling | Yes |
| Number of front fans supported (max) | 2 |
| Front fans diameters supported | 140, 120 |
| Rear fans diameters supported | 120 |
| Top fans diameters supported | 120 |
| Bottom fans diameters supported | 120 |
| Number of rear fans supported (max) | 1 |
| Number of top fans supported (max) | 2 |
| Number of bottom fans supported (max) | 1 |
| Rear fans installed | 1x 120 mm |
| Liquid cooling capability | Yes |
| Rear radiator sizes supported | 120 |
| Front radiator sizes supported | 120, 240 |

### Storage

| Feature | Value |
|---|---|
| Supported HDD sizes | 2.5, 3.5 |

### Weight & dimensions

| Feature | Value |
|---|---|
| Weight | 3.7 kg |
| Height | 378 mm |
| Width | 230 mm |
| Depth | 387 mm |

### Packaging data

| Feature | Value |
|---|---|
| Package weight | 4700 g |
| Package depth | 435 mm |
| Package height | 461 mm |
| Package width | 276 mm |

### Logistics data

| Feature | Value |
|---|---|
| Harmonized System (HS) code | 84733080 |

## FAQ

### How much does the PC case Cooler Master MasterBox Q300L cost, and is it available for purchase?

The price is 46.49 € (valid at the time of publication and already includes all taxes). The item is available for order — 162 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 13.07.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All Cooler Master products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized Cooler Master service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

### How can I tell if this product suits my needs?

When making a choice, we recommend paying attention to the key features: type, form factor, number of 3.5" bays, number of 2.5" bays, number of 5.25" bays, side window, power supply included, usb 2.0 ports quantity, usb 3.2 gen 1 (3.1 gen 1) type-a ports quantity, weight, supported motherboard form factors, material, product colour, compatibility with your devices or usage conditions, material quality, functionality, and warranty terms. These characteristics will help you determine how well the model meets your needs.

### Where can I download the instructions for PC case Cooler Master MasterBox Q300L?

You can download the instructions in PDF format from the “Instructions” section on the product description page. The file contains complete information about installation, setup, and usage.

## Image

https://aio.lv/img/cache/product/562027/64891265_large.webp