Cooler Master RC-342-KKR400-U3

Overview

The Cooler Master RC-342-KKR400-U3 is a mini-tower computer case designed to provide a compact and efficient solution for building a versatile PC. It comes with a reliable 400 W power supply pre-installed, supporting micro-ATX and Mini-ITX motherboards to accommodate a range of setups from office workstations to home-theater or light gaming systems. Its design balances space-saving dimensions with ample room for drives and expansion cards, making it a practical choice for users who need a capable system without a large footprint.

Key features

• Includes a dependable 400 W power supply mounted at the top, simplifying the build process by providing essential power from the start
• Supports both micro-ATX and Mini-ITX motherboards, offering flexibility for different system sizes and purposes
• Mesh front panel combined with space for up to three fans ensures effective airflow to keep components cool during operation
• Accommodates two full-size 5.25-inch external optical drives and five internal 3.5-inch hard drives, allowing extensive storage options
• Front I/O panel features two USB 2.0 ports and an eSATA port for convenient access to peripherals and high-speed external storage
• Four full-height expansion slots provide room for graphics cards, sound cards, or other add-ons to customize the system
• Compact and sturdy steel chassis with a plastic front panel fits well in small spaces such as dorm rooms, home offices, or retail counters

Key specs

• Power supply: 400 W, top-mounted
• Motherboard support: micro-ATX and Mini-ITX
• Drive bays: two 5.25-inch external, five 3.5-inch internal
• Expansion slots: four full-height
• Cooling: mesh front panel, supports up to three fans
• Front I/O ports: two USB 2.0, one eSATA
• Case type: mini-tower

Connectivity and compatibility

The front panel provides easy access to two USB 2.0 ports, ideal for connecting keyboards, mice, or flash drives without reaching behind the case. The inclusion of an eSATA port offers a fast connection for external hard drives, which is useful for quick backups or transferring large files. Compatibility with micro-ATX and Mini-ITX motherboards means this case supports a wide range of components, from budget office setups to more specialized compact builds.

Ideal uses and environments

This mini-tower case is well suited for users who need a reliable and space-conscious PC enclosure. It works well in home offices where desk space is limited, dorm rooms where compactness is essential, and small retail or reception areas where a discreet yet functional system is required. Its storage capacity and expansion options also make it a strong choice for light gaming, media servers, or small business applications that demand flexibility without complexity.

Orders are processed within 2 business days, which includes verification, packing, and dispatch. Shipping costs are calculated at checkout based on destination, total weight, and selected speed. Free shipping applies to carts over $100 (excluding heavyweight items). All available options and final pricing are clearly shown before payment so you can choose the service that best fits your needs.

Deliveries are handled by major carriers such as USPS, UPS, and FedEx. Estimated delivery times are displayed at checkout and may vary depending on service level and location. Please note that these are estimates and can be affected by weather, holidays, or carrier volume. Once your order ships, you’ll receive a tracking number for real-time updates from pickup to final delivery.

Providing an accurate shipping address helps prevent delays, and changes may be limited once the order has been dispatched. P.O. boxes are supported only when permitted by the selected carrier. Packaging and handoff are optimized to protect items during transit, though oversized or high-weight products may require special handling. All shipping methods and any related constraints are clearly shown during checkout.

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Returns are accepted within 30 days of delivery. Items must be unused, in the same condition received, with tags, manuals, accessories, and original, unaltered packaging. Any item kept will be deducted from the refund. Start a return by sending us an email. Items sent back without approval may be refused or returned to the sender.

Some items are not returnable: opened TVs/combos/monitors 37″+, opened computers or software, electronic downloads, opened consumables (film, paper, bulbs, media, ink), custom or modified computers, special-order or “nonreturnable” items, submerged underwater gear, and opened educational media.

After inspection, refunds are issued to the original payment method; allow 5–7 business days for the credit to post. Shipping, handling, customs duties, and import taxes are nonrefundable. If an item is used, incomplete, or not in original condition, a 30% restocking fee may apply. Direct exchanges are not offered; purchase the replacement and return the original for a refund.

We act solely as a reseller. Any product warranty is provided and administered by the manufacturer, not by our store. That means eligibility, coverage, and outcomes are determined by the manufacturer’s policy for each brand and model. Before purchasing, we recommend reviewing the warranty terms on the manufacturer’s website or in the product documentation to confirm what is covered and for how long.

If you need warranty service, please file the claim directly with the manufacturer. They may require proof of purchase, the product serial number, original packaging, photos, or basic troubleshooting. Some brands ask you to register the product or obtain a case number before shipping it for repair or replacement. We don’t submit or approve claims, but we can point you to the correct support links and contact details.

Keep your invoice and packaging in a safe place, and report any functional issues to the manufacturer as soon as they appear. If you’re unsure whether a problem is covered, the manufacturer’s support team can confirm next steps and timelines. While we cannot intervene in decisions or outcomes, we’re happy to provide purchase documentation or guidance so you can move through the warranty process smoothly.

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