This article covers NZXT H2 Flow Black Mini-ITX PCケース CI-H21FB-01 CS9514.

Overview

The NZXT H2 Flow Black is a compact Mini-ITX tower PC case that packs impressive expandability into just 20.7 liters. Its hybrid side panel combines tempered glass with ultra-fine mesh, offering a clear view of your components while maintaining excellent airflow. The case supports graphics cards up to 331mm and radiators up to 280mm, making it suitable for high-end builds despite its small footprint. A PCIe Gen 5.0 riser cable for vertical GPU mounting is included standard, ensuring next-gen graphics cards perform at their best. This case is ideal for gamers and creators who need a space-saving yet powerful system. The steel, glass, and mesh construction feels robust, and internal cable routing points with Velcro straps help keep the build tidy.

Compatibility Guide

The H2 Flow is designed exclusively for Mini-ITX motherboards. Power supply must be SFX or SFX-L form factor, with a maximum length of 130mm. Storage is limited to two 2.5-inch drives (SSD/HDD); no 3.5-inch bays or optical drives are supported. Graphics card clearance is up to 331mm length, 65mm thickness, and 150mm width. CPU cooler height is limited to 75mm, so low-profile air coolers or liquid cooling is required. Front I/O includes one USB 3.2 Gen2x2 Type-C port, two USB 3.2 Type-A ports, and a headset jack.

Product Info

The NZXT H2 Flow Black (model CI-H21FB-01 CS9514) launched in 2025, targeting the mid-to-high-end compact PC market. It measures 181×263×434mm (W×D×H) and weighs 4.55kg. The chassis is made of steel, tempered glass, and mesh. Cooling is handled by two pre-installed F120Q case fans at the top. Additional fan support: two 120/140mm front fans and two 120mm top fans. The front radiator can accommodate up to 280mm. The included PCIe Gen 5.0 riser cable supports vertical GPU mounting.

Best Use Cases

Compact Gaming PC Builds: Combine with a Mini-ITX board and a GPU up to 331mm for a powerful gaming rig. The vertical GPU mount with Gen 5.0 cable enhances aesthetic and performance. Space-Conscious Workstations: Perfect for desks with limited space. Supports 280mm AIO coolers for quiet operation. * Showcase Builds: The hybrid side panel highlights premium components like NZXT Kraken Elite displays while maintaining airflow.

Things to Consider

This case is strictly Mini-ITX only; ATX or Micro-ATX boards will not fit. CPU cooler height is extremely limited (75mm), so almost all tower air coolers are incompatible. Water cooling is the practical choice. Only SFX/SFX-L power supplies are supported; standard ATX PSUs cannot be installed. Storage is limited to 2.5-inch drives, so if you need multiple 3.5-inch HDDs, look elsewhere. When using a long GPU, be mindful of airflow – ensure front intake fans are configured properly.

Product Disclosure (Amazon)

  • Manufacturer: NZXT
  • Seller: Amazon.co.jp
  • Fulfilled by: Amazon.co.jp
  • ASIN: B0FJD21RLV
  • Note: This article covers a manufacturer-made product based on Amazon listing details.