Wathai
Wathai 40mm x 20mm 12V Dual Ball Bearing DC Brushless Cooling Fan 2pin 4020
Bottom line: The Wathai 40mm x 20mm 12V Dual Ball Bearing DC Brushless Cooling Fan: Dual ball bearings rated for a 50,000-hour lifespan; main trade-off: 26dBA is audible at full 6000RPM in quiet rooms.
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Pros & Cons
Pros
- ✓ Dual ball bearings rated for a 50,000-hour lifespan
- ✓ Compact 40x40x20mm frame fits tight PSU and inverter bays
- ✓ 6000RPM spins out 7.85CFM airflow for a 40mm fan
- ✓ Ships with mounting screws, nuts and a 20cm XH2.54 lead
Cons
- ✗ 26dBA is audible at full 6000RPM in quiet rooms
- ✗ XH2.54-2Pin plug needs an adapter for standard fan headers
- ✗ No PWM or speed control, runs at full tilt only
- ✗ 7.85CFM airflow is modest for high-heat equipment
SpecPicks Verdict
SpecPicks scored Wathai 40mm x 20mm 12V Dual Ball Bearing DC Brushless Cooling Fan… using a rating × review-volume × price-fit model applied to published specs and reviews across the power supplies category. Wathai's power supplies 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 power supplies 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
- 40x20mm size fan for replacing fans in inverter and storage equipmentcs such as PSU，battery charger, 3D printer, switches, NAS , DVRs etc
- The 40mm DC brushless fan operates at 12V, ideal for cooling electronic equipment. This compact 40x40x20 12V fan ensures efficient cooling for various electronics, making it a reliable choice for 12V cooling needs
- Dual ball bearing providing reliable performance for prolonged periods with a lifespan of 50,000 hours
- Rated Voltage:12V 0.05A; Speed: 6000RPM; Air flow: 7.85CFM; Noise:26dBA; Connecter: XH2.54-2Pin; Cable Length: 20cm Or 8 inche
- 1 Piece fan and mounting screws & nuts; Dimension: 40mm(L) x 40mm(W) x 20mm(H) / 1.58x1.58x0.79 in. per fan
Full Specifications
| Brand | Wathai |
|---|---|
| Model | 4020B12V2P2.5 |
| Voltage | 12 volts_of_direct_current |
| Material | Plastic |
| Dimensions | 1.58x1.58x0.79 in |
| Unit Count | 1 Count |
| Noise Level | 26 db |
| Part Number | 4020B12V2P2.5 |
| Material Type | Plastic |
| Rated Voltage | 12V 0.05A; Speed: 6000RPM; Air flow: 7.85CFM; Noise:26dBA; Connecter: XH2.54-2Pin; Cable Length: 20cm Or 8 inche |
| Cooling Method | fan cooling |
| Number of Items | 1 |
| Number of Packs | 1 |
| Air Flow Capacity | 7.85 cfm |
| Compatible Devices | Amplifier, Desktop, Gaming Console, Printer, Projector |
| Power Connector Type | 2-Pin |
| Maximum Rotational Speed | 6000 rpm |
| Item Dimensions L x W x H | 1.56"L x 1.58"W x 0.79"H |
Ready to buy?
Wathai 40mm x 20mm 12V Dual Ball Bearing DC Brushless Cooling Fan 2pin 4020 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.
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