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White mechanical keyboard PCB with black switches and RGB LEDs

Corn Electronics

Corn Electronics GK21S Gaming Keyboard Black Switch White 32 bit MCU Bluetooth 5.1 750mAH

SKU CH-YFSJ-KMMZT

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

  • Key SwitchBlack Switch
  • Keyboard ColorWhite

Key Switch Type Black Switch

Keyboard Color White

  • 32-bit MCU and 8 MB flash deliver responsive custom firmware
  • Bluetooth 5.1 plus Type-C USB give flexible dual-mode connectivity
  • Hot-swappable Kailh sockets let you change switches without soldering
  • 8 million-colour per-key RGB with music-reactive lighting effects
  • 750 mAh battery supports extended wireless gaming sessions

GK21S kit with hot-swappable PCB

The Corn Electronics GK21S is a custom mechanical keyboard kit built around a hot-swappable PCB that accepts three- or five-pin MX-style switches. It ships with black linear switches installed and a white case, aimed at enthusiasts who want to assemble or modify their own layout without soldering.

Dual-mode Type-C and Bluetooth 5.1

Connectivity runs through a detachable Type-C cable or Bluetooth 5.1, powered by a built-in 750mAH lithium cell. The 32-bit MCU and 8M flash handle lighting and macro storage with negligible draw, so the board stays cool and silent whether wired or wireless.

Per-key RGB driver with music rhythm

Three 256×256×256 LED driver chips produce 16.8 million colours per key and enable reactive music-rhythm effects. The firmware supports three programmable layers and custom macros, while the anti-RGB lamp position and plate-mount stabiliser cutouts keep switch compatibility broad.

Highlights

  • 32-bit MCU and 8 MB flash deliver responsive custom firmware
  • Bluetooth 5.1 plus Type-C USB give flexible dual-mode connectivity
  • Hot-swappable Kailh sockets let you change switches without soldering
  • 8 million-colour per-key RGB with music-reactive lighting effects
  • 750 mAh battery supports extended wireless gaming sessions

Specifications

Key SwitchBlack Switch
Keyboard ColorWhite

Other versions of this model

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Questions about this item

How do I install the GK21S keyboard and what step do people often miss?

Connect via the Type-C USB cable or pair using Bluetooth 5.1, then install the driver software to enable macro programming and the three customisable layers; the step most people skip is installing the driver before customising keys.

What maintenance or replacement will the GK21S need over time?

The hot-pluggable Kailh sockets let you swap individual MX-compatible switches — Cherry, BOX or G-type — without soldering, and the 750mAH lithium battery can be recharged via Type-C whenever runtime drops.

What limit appears first during extended gaming sessions on the GK21S?

The 750mAH battery will deplete first under sustained wireless use with RGB lighting active; plug in the Type-C cable to continue without interruption while the cell recharges.

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