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Compact magnetic phone cooler with RGB lighting, 69.5g

shijianwy K21 Type A magnetic phone cooler 69.5g

SKU CH-P5SX-93S6X

A magnetic semiconductor cooler with AI temperature control, digital display, four operating modes and RGB lighting attaches to MagSafe iPhones 12 to 16, Android phones, tablets and Switch.

  • Accessory categoryType A
  • In the boxPhone cooler*1N
  • AI smart chip adjusts fan speed in real time
  • Semiconductor refrigeration reaches 0 °C in 25 seconds
  • Magnetic attachment fits iPhone 12 to 16 and MagSafe cases
  • Clip and magnetic ring extend use to iPad, Samsung, Pixel and Switch
  • Weighs 69.5 g with digital display and four selectable cooling modes

Magnetic Phone Cooler K21 Type A

The shijianwy K21 Type A is a lightweight magnetic cooler that clamps to the back of a smartphone or tablet using MagSafe attraction or an included clip-and-ring kit. It targets mobile gamers, streamers and anyone who needs rapid temperature reduction during extended sessions without adding bulk. Weighing 69.5 g, it draws power from a USB connection and is designed for hands-free use on iPhone 12 through 16 series, recent iPad models, Samsung Galaxy S23 and S24 Ultra, Google Pixel 7 through 9 Pro, and Nintendo Switch.

Semiconductor Cooling With AI Temperature Control

A built-in TEC module and seven-blade fan drop the contact surface toward 0 °C in roughly 25 to 30 seconds at 25 °C ambient. An AI smart chip monitors the contact temperature in real time and automatically adjusts fan speed, while over-temperature protection prevents excessive cold. Four selectable modes — AI auto, P1 for reading, P2 for video, P3 for gaming and broadcasting — match cooling intensity to the workload, and a digital display shows the active setting.

Upgrade From Passive Stands Or No Cooling

Users moving from passive metal stands, simple clip-on fans or no cooler at all gain active refrigeration that reacts to load changes in seconds. The jump is worth it when sustained gaming, video broadcasting or heavy multitasking causes throttling, dropped frames or uncomfortable surface heat. Buyers who need multi-device simultaneous cooling, built-in battery operation or a cooler that fits inside a closed laptop lid will not find those capabilities here.

How it compares

Measured against everything we stock in Laptop Cooling Stands & Fans, at today’s prices. Recalculated every night.

Price $27.99
Pricier than about 65% of the 6,190 comparable items (median $20.99).

Specifications

Product
Brand nameShijianwy
Model nameK21
Part numberK21
Accessory categoryType A
In the box
In the boxPhone cooler*1N

Questions about this item

Will the K21 Type A cooler stay attached to an iPhone 13 Pro Max during use?

Yes, the magnetic attraction works directly with MagSafe-compatible cases such as the iPhone 13 Pro Max, holding the 69.5 g cooler firmly without clips.

How can I confirm the cooler is actively lowering the phone temperature after I switch it on?

The built-in digital display shows the current mode — AI, P1, P2 or P3 — and the RGB lighting changes colour with each mode, giving immediate visual confirmation that the semiconductor module is running.

Does the package include a magnetic ring for non-MagSafe phones, and is a separate power cable required?

The box contains the phone cooler only; the magnetic ring for Android or older iPhone models is not included, and the unit draws power via its integrated USB connector so no extra cable is needed.

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