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Lian Li B4-mATX Mesh PC-B4W SFF Dual-Orientation 21.3L Micro-ATX Case - Black

Description

The Lian Li B4 DAN Mesh mATX Case delivers a compact 21.3-litre volume while accommodating full-sized hardware, including graphics cards up to 358 mm in length. This steel chassis optimises desktop space without forcing you to compromise on component selection or cooling performance.

Small footprint without Mini-ITX compromises

Designed for builders who want a space-conscious system but prefer the affordability and expansion options of a micro-ATX motherboard, this chassis supports both Micro-ATX and Mini-ITX form factors. Measuring 420 x 191 x 288 mm, it occupies a fraction of the space of traditional mid-tower cases. The four expansion slots provide ample room for multi-slot PCIe cards, giving you the flexibility to install dedicated capture cards, sound cards, or high-speed storage expanders alongside your primary graphics card.

Room for triple-slot graphics cards and standard ATX power supplies

Despite its small form factor, this case accommodates high-end hardware configurations. You can install graphics cards up to 358 mm in length, allowing compatibility with large triple-fan GPUs. Power supply options are highly flexible; the internal layout supports standard ATX power supplies up to 140 mm in length, as well as SFX and SFX-L units. This dual-PSU compatibility means you can reuse an existing ATX power supply or opt for a compact SFX unit to maximise internal clearance for other components.

Flexible liquid and air cooling configurations

Cooling configurations scale based on your chosen power supply. When paired with an SFX PSU, the side bracket supports liquid cooling radiators up to 360 mm, 280 mm, or 240 mm. Opting for a standard ATX PSU allows for a 240 mm side radiator. For air cooling, the case supports CPU coolers up to 162 mm in height, which increases to 168 mm if you remove the side fan bracket. Airflow is supported by comprehensive fan mounting options across the chassis:

  • Top: Two 120 mm fans
  • Side (with SFX PSU): Three 120 mm or two 140 mm fans
  • Side (with ATX PSU): Two 120 mm fans
  • Front (with SFX PSU only): One 120 mm slim fan
  • Bottom: Three 120 mm or two 140 mm fans
  • Rear: One 120 mm fan

To jumpstart your build, the case includes two pre-installed 120 x 120 x 15 mm slim fans. Dust management is handled by a magnetic filter on the bottom panel to protect your intake.

Modern front-panel connectivity for daily devices

The front I/O panel provides quick access to high-speed ports and audio connections. It features:

USB Type-C 1x USB 3.2 Type-C
USB Type-A 2x USB 3.0 Type-A
Audio 1x Audio Combo Jack
Controls 1x Power Button

This layout ensures rapid data transfer speeds for external drives and easy connection of modern peripherals without reaching behind the chassis.

Storage and warranty reliability

Storage options include a dedicated front mount for one 2.5-inch SSD, and a bottom mount that supports either one 3.5-inch HDD or an additional 2.5-inch SSD. This steel-constructed chassis is backed by a one-year warranty, ensuring long-term reliability for your compact desktop build.

Product specifications

  • Case form factor: Micro Tower
  • Contains button battery: No
  • Motherboard form factor: Micro ATX

LIAN LI

Lian Li B4-mATX Mesh PC-B4W SFF Dual-Orientation 21.3L Micro-ATX Case - Black

Model: PC-B4X SKU: 10090803

IT

Price:

$132

Key features

  • 21.3L
  • mATX
  • Mesh

Getting your item

Delivery available

Returns policy

Returns policy

Warranty guide

Warranty guide