This article covers Thermaltake Chassis Stand Kit for The Tower 300 Black 横置き用 スタンド・ボトムカバーキット ブラック AC-074-ON1NAN-A1 CS8905.

Overview

Thermaltake's Chassis Stand Kit for The Tower 300 Black (model AC-074-ON1NAN-A1, also known as CS8905) is a dedicated accessory that lets you convert the iconic octagonal Tower 300 case from vertical to horizontal orientation. The kit includes a custom-shaped stand and a matching bottom cover, allowing you to place the case on its side while maintaining a clean, integrated look. Installation is straightforward: remove the original feet from the case, attach the bottom cover, and mount the stand. Rubber mats on all contact points prevent scratches and reduce vibration. The entire kit is finished in black to match the Tower 300 Black edition.

Compatibility Guide

This kit is designed exclusively for the Thermaltake The Tower 300 series. The case itself supports Mini ITX motherboards, and the stand does not impose any additional motherboard restrictions. However, when placed horizontally, internal airflow patterns change—pay attention to CPU cooler orientation and GPU placement. The stand adds approximately 145mm to the case height (when laid flat) and extends the depth to about 459mm.

Product Info

Released in early 2024, this accessory kit is available through Japan for around ¥4,591 (tax included). It carries a 3-year warranty through Thermaltake's official Japanese distributor. The stand and cover are made of plastic, with a total weight of 694g. As a first-party accessory, it offers perfect color matching and fitment that third-party alternatives cannot guarantee.

Best Use Cases

Space-constrained desks: Horizontal placement reduces the case's height, making it easier to fit under a monitor riser or inside a shelf. Showcase builds: The angled horizontal layout creates a distinctive visual that highlights internal components, ideal for gaming or workstation rigs. * Existing Tower 300 owners: If you already own the case and want to change its orientation without buying a new chassis, this kit is the simplest and most aesthetically consistent solution. ## Alternatives
Generic horizontal stands from brands like Lian Li or Cooler Master are cheaper but lack the precise fit and bottom cover that this kit provides. Without the cover, the original bottom of the case (now a side panel) would be exposed, looking unfinished. The Thermaltake kit also includes rubber mats and uses the same screw holes as the original feet, so no drilling or modification is needed.

Things to Consider

This kit is only compatible with the Thermaltake The Tower 300—it will not work with any other case. When switching to horizontal orientation, be aware that top-mounted fans or radiators may become side-mounted, potentially affecting thermal performance. You'll also need to reuse the dust filter from the case's original bottom panel, as the kit does not include one. At around ¥4,600, it's not a budget item, but for owners who value design consistency and ease of installation, it's a worthwhile investment.

Product Disclosure (Amazon)

  • Manufacturer: Thermaltake
  • Seller: Amazon.co.jp
  • Fulfilled by: Amazon.co.jp
  • ASIN: B0CV5JBPCQ
  • Note: This article covers a manufacturer-made product based on Amazon listing details.