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Black compact mechanical keyboard with RGB backlighting and hot-swappable switches

Corn Electronics

Corn Electronics GK21S Hot-Swappable Mechanical Gaming Keyboard Black Switch

SKU CH-NEAH-BYHFM

A hot-swappable mechanical keyboard with Black switches, Bluetooth 5.1 dual mode, 16.8M RGB lighting and a 750mAh battery

  • Key SwitchBlack Switch
  • Keyboard ColorBlack

Key Switch Type Black Switch

Keyboard Color Black

  • 32-bit MCU enables fast response and custom macro layers
  • Bluetooth 5.1 plus Type-C cable gives wireless and wired freedom
  • Hot-swappable Kailh sockets let you change switches without soldering
  • 8 million RGB colours with music-reactive lighting effects
  • 750 mAh battery powers extended wireless gaming sessions

Compact numpad for custom builders

The Corn Electronics GK21S is a 21-key mechanical numpad kit designed for enthusiasts who want a programmable input device with hot-swappable switches. It arrives with black linear switches installed and a black chassis, ready for immediate use or further customisation with compatible MX-style switches.

Low-draw wireless and wired operation

Bluetooth 5.1 connectivity pairs with a Type-C USB cable for dual-mode operation, powered by a 750 mAh lithium battery. The 32-bit MCU and 8 MB flash handle lighting and macro processing without noticeable latency, while the PCB-mounted stabilisers keep key feel consistent during extended sessions.

Per-key lighting and macro layers

Three 256-channel LED drivers produce 16.8 million colours with south-facing LEDs that shine through compatible Cherry, BOX and Gateron switches. The firmware supports music-reactive effects, sound control and three programmable layers for custom macros, all configurable via the supplied driver software.

Highlights

  • 32-bit MCU enables fast response and custom macro layers
  • Bluetooth 5.1 plus Type-C cable gives wireless and wired freedom
  • Hot-swappable Kailh sockets let you change switches without soldering
  • 8 million RGB colours with music-reactive lighting effects
  • 750 mAh battery powers extended wireless gaming sessions

Specifications

Key SwitchBlack Switch
Keyboard ColorBlack

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Questions about this item

How do I install switches on the GK21S hot-swappable PCB?

Align each switch with the Kailh hot-swap sockets and press straight down until seated; the PCB accepts three-pin and five-pin MX-style switches including Cherry, BOX and Gateron types.

What maintenance will the GK21S require over time?

The 750 mAh lithium battery will eventually lose capacity and need replacement; switches can be pulled and swapped at any time without soldering.

What limit appears first during long wireless sessions on the GK21S?

The 750 mAh battery will deplete before any thermal or firmware limit is reached during sustained Bluetooth 5.1 use.

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