Geekworm
Geekworm Power Supply for Raspberry Pi 4
Bottom line: The Geekworm Power Supply for Raspberry Pi 4 ($9.99 on Amazon as of 2026-10-22 10:13 UTC, orderable but not in stock): UL Listed 5.1V/4A output prevents Pi 4 under-voltage warnings; main trade-off: USB-C only, no micro-USB for older Pi 3 or Zero W.
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*Price sourced from Amazon.com. Last updated 2026-10-22. Price and availability subject to change.
Pros & Cons
Pros
- ✓ UL Listed 5.1V/4A output prevents Pi 4 under-voltage warnings
- ✓ 20W (5V 4A) headroom powers Pi 4 plus HATs and USB peripherals
- ✓ 5 protections: over-voltage, under-voltage, over-temp, over-current, short
- ✓ Works with NASPi, X735, X728, X306 and other Geekworm boards
Cons
- ✗ USB-C only, no micro-USB for older Pi 3 or Zero W
- ✗ Fixed 1.2m cable, not detachable if you need more reach
- ✗ US plug only, needs an adapter outside North America
- ✗ 5V 4A overkill for low-draw boards like Pi Zero 2
Manufacturer description
About this item Compatibility: USB-C Type C power adapter designed and tested for the Raspberry Pi 4 Model B 1GB/2GB/4GB/8GB Version; Also support NASPi/X-C1/X825/X735/X728/X708/X703/X306 expansion board/Retroflag PiStation Case/Orange Pi 5/5B/4B/3B/Pi 800/4 LTS/3 LTS/Zero 2/Zero 3 Power Input: 100-240V AC, 50-60Hz, 0.8A Max; Output: 5V 4A 20W; Cable length: 1.2 m / 47.24 inches UL Listed 5.1V 4A USB-C Power Adapter for Raspberry Pi 4B: Certified Safety and Stable Power Supply to Prevent Under-Voltage Warnings Power Supply Functions: Over voltage protection; Under voltage protection; Over…
SpecPicks Verdict
SpecPicks scored Geekworm Power Supply for Raspberry Pi 4 using a rating × review-volume × price-fit model applied to published specs and reviews across the single-board computers category. Geekworm's single-board computers lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
Common buyer scenarios for single-board computers of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Key Features
- Compatibility USB-C Type C power adapter designed and tested for the Raspberry Pi 4 Model B 1GB/2GB/4GB/8GB Version; Also support NASPi/X-C1/X825/X735/X728/X708/X703/X306 expansion board/Retroflag PiStation Case/Orange Pi 5/5B/4B/3B/Pi 800/4 LTS/3 LTS/Zero 2/Zero 3
- Power Input 100-240V AC, 50-60Hz, 0.8A Max; Output 5V 4A 20W; Cable length 1.2 m / 47.24 inches
- UL Listed 5.1V 4A USB-C Power Adapter for Raspberry Pi 4B Certified Safety and Stable Power Supply to Prevent Under-Voltage Warnings
- Power Supply Functions Over voltage protection; Under voltage protection; Over temperature protection; Over current protection; Short circuit protection
- Packing List 1x 5V 4A US Plug Type-C Power Supply
Full Specifications
| ASIN | B09J856PND |
|---|---|
| Brand | Geekworm |
| Color | Black |
| Wattage | 20 watts |
| Amperage | 4 Amps |
| Portable | No |
| Power Plug | Type A - 2 pin (North American) |
| Unit Count | 1.0 Count |
| Item Weight | 131 Grams |
| Manufacturer | Geekworm |
| Model Number | TB-2021-35 |
| Power Source | Corded Electric |
| Input Voltage | 240 Volts |
| Mounting Type | Wall Mount |
| Built-In Media | 1x 5V 4A US Plug Type-C Power Supply |
| Connector Type | usb |
| Output Current | 4 Amps |
| Output Voltage | 5 Volts |
| Frequency Range | 50-60 Hz |
| Number of Items | 1 |
| Full listing title | Geekworm Power Supply for Raspberry Pi 4, 20W 5V 4A USB C Power Adapter Type C Charger UL Listed Compatible with Raspberry Pi 4 Model B/Orange Pi 5/NASPi/KVM-A3/KVM-A8/X651/X735/X306/X728/X703 |
Ready to buy?
Geekworm Power Supply for Raspberry Pi 4, 20W 5V 4A USB C Power Adapter Type C Charger UL Listed Compatible with Raspberry Pi 4 Model B/Orange Pi 5/NASPi/KVM-A3/KVM-A8/X651/X735/X306/X728/X703 is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-10-22. Price and availability subject to change.
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