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CiT S503 Desktop Case

CCL Code: CAS2667
Manufacturer Code: CITS503
| Manufacturer: CiT

Key Features:

  • PSU not included
  • 1 x 5.25" External Bay(s)
  • 1 x 2.5", 1 x 3.5" HDD Bay(s)
  • Max MB Size: Micro-ATX

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The CIT S503 slim desktop case is notably strong for its modest size, creating the perfect case for System Integrators. The CIT S503 features a full tool-less design, with 2 x USB 2.0 and 2 x USB 3.0 and a quick release ODD/HDD housing system for fast installation with minimal effort. The included base allows for vertical installation of the S503, the CIT S503 supports Micro ATX or Mini ATX form factor motherboards and with its low profile body and sleek styling, the S503 blends seamlessly into any environment as a silent PC, versatile Home Theater PC or a powerful workstation.


  • Max PSU length: 174mm

Case Specifications

  • Form Factor: Desktop, Micro ATX
  • Motherboard Support: Micro ATX, Mini ITX
  • PSU Support: Flex
  • PSU Location: Top
  • Gaming Case: No
  • Water Cooling: Not Water Cooling Ready
  • Body Material: 0.6mm SGCC
  • Front Bezel Material: Plastic
  • Side Panel: Blank
  • External Bays: 1 x 5.25” External, 1 x 3.5” External
  • Internal Bays: 1 x 3.5” Internal, 1 x 2.5” Internal
  • Expansion Slots: 4 x Half-Height
  • Cooling Front: Space for 1 x 80mm fan (inc.)
  • Cooling Top: None
  • Cooling Rear: None
  • Cooling Side: None
  • Cooling Bottom: None
  • IO Ports: 2 x USB 3.0, 2 x USB 2.0, 1 x HD Audio, 1 x Microphone
  • GPU Max Length: 190mm
  • CPU Cooler Maximum Height: 82mm
  • Front Bezel Colour: Black/Grey
  • Body Colour: Black
  • PSU Included: No

General Specifications

  • Manufacturer Part Number: CITS503
  • EAN Number: 5055492404510
  • Has Mains Plug: No
  • Colour: Black
  • What's In The Box: Case, Screws, Manual, ODD mounting bracket, 3.5" mounting bracket
  • Unit (Product) Dimensions (mm): 332mm x 101mm x 380mm (W x H x D)
  • Packaging Dimensions (mm): 410mm x 468mm x 181mm (W x H x D)
  • Net Weight (KGs): 3.1 KGs
  • Gross Weight (KGs): 3.4 KG

Main Features

  • Full tool-less designed chassis
  • Ultra thin desktop micro ATX case, supports various micro M/B
  • Put both vertical or horizontal
  • Quick release side panel
  • Pad lock, Kensington lock, Alarm Switch optional


External Expansion Bays 1 x 3.5 inch • 1 x 5.25 inch
Internal Expansion Bays 1 x 2.5 inch • 1 x 3.5 inch


Expansion Slots 4


USB Ports 2 x USB 2.0 • 2 x USB 3.0
Microphone In Port 1


Cooling System Cooling Front: Space for 1 x 80mm fan (inc.)


Form Factor Desktop Case
Case Colour Black
Motherboard Compatibility Micro ATX • Mini ITX
In The Box Case • Screws • Manual • ODD mounting bracket • 3.5 inch mounting bracket

Key Features

Firewire No
Main Colour Black
Case Type Desktop
USB 3.0 Support Yes
Case Form Factor Desktop
Power Supply Included No
Optimised for Home
80Plus Rated No
PSU Form Factor TFX
Display Model in Showroom No
L.E.D Fan No LED
Internal 3.5" Bay 1
External 5.25" Bay 1
Internal 2.5" Bay 1
Micro-ATX Yes
Built-in Card Reader No
USB Type-C Support No
Front HDMI No
Side Panel Type Solid
Front Audio Type Separate
Maximum Motherboard Size Supported Micro-ATX


Warranty 1 Year

Item Details

Manufacturer CiT
Manufacturer Code CITS503
EAN 5055492404510
Condition New

Warranty Information

Warranty 1 Year

Manufacturer Information

Manufacturer CiT
Manufacturer Code CITS503
Questions and Answers

Do you have you a question about the CiT S503 Micro ATX Desktop Case?

Q: The 'Specification' page says this will fit an ATX PSU. Is this true?
Answer by Website User on 5th March 2020
The listing was incorrect and has now been corrected. - Kristian N
0 customers found this answer helpful.
Post Answer
Q: CiT S503 Desktop Black Case - what psu fits this case ?
Answer by Website User on 16th February 2018
This fits a FLEX form factor PSU but we do not sell these.
1 customer found this answer helpful.
Answer by kevin on 31st March 2018
This is not true. i purchased a flex psu based on this info and it is far too small. You need a TFX psu.
5 customers found this answer helpful.
Answer by Website User on 27th August 2021
I used GameMax GT-300W 300W 80+ Bronze PSU
0 customers found this answer helpful.
Post Answer