3DFitBud A420S Simple Step Counter Pedometer
- Display Size: 1.7 inches
- Size: One Size
- Battery Average Life: 365 days
- Sensor Type: 3D Tri-Axis Sensor
Last refreshed Jul 5, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A straightforward pick for anyone who wants an accurate daily step count with minimal setup and no app required.
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ASIN: B07DWCVLT1Model: A420SCategory: Pedometers
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Overview
The 3DFitBud A420S is a clip-on pedometer built to do one thing: count steps. It ships with a battery pre-installed and uses a 3D tri-axis sensor to read steps regardless of how it's carried, on a hip clip, lanyard, or in a pocket. The design skips apps and menus entirely.
Stripped down to one job, this step counter carries no heart rate, GPS, or app sync in its spec sheet, and that is the point for buyers who found smartwatches overwhelming. A large display and single rear button keep the learning curve close to zero. It suits anyone who just wants a number at the end of the day.
- 3D tri-axis step sensor
- Extra-large digital display
- Clip and lanyard included
- Battery pre-installed, up to 12-month life
Who it's for
Kids, seniors, and anyone who wants a plain step count without an app will get the most from this. Runners or cyclists tracking pace, heart rate, or GPS routes should look elsewhere.
Pros and cons
- One-button operation with no setup
- Large display readable at a glance
- Battery pre-installed, rated up to 12 months
- Clips, lanyard, or pocket wearing options
- Steps only, no distance, calories, or app data listed
- No advanced metrics for structured training
Performance notes
The 3D tri-axis sensor is designed to register steps whether the unit sits flat in a pocket, hangs from the included lanyard, or clips to a waistband, since there's no feedback until you check the display. It auto-sleeps when idle and wakes on movement to preserve the pre-installed battery, rated for up to 12 months.
Specifications
| Brand | 3DFitBud |
|---|---|
| Model | A420S |
| Dimensions & fit | |
| Display Size | 1.7 inches |
| Size | One Size |
| Item Weight | 0.05 pounds |
| Item Dimensions L X W X H | 2.4 × 1.6 × 0.4 inches |
| Power & efficiency | |
| Battery Average Life | 365 days |
| Battery Description | CR2032 Button-Cell Battery |
| Construction & materials | |
| Material Type | Acrylonitrile Butadiene Styrene (ABS) |
| Color | Pink |
| Compatibility & installation | |
| Compatible Devices | No Bluetooth or Smartphone connections required |
| Included components | |
| Unit Count | 1 |
| Number Of Packs | 1 |
| Warranty & support | |
| Warranty Description | 1.5 years |
| Software Update Supported To Date | unknown |
| Other details | |
| Sensor Type | 3D Tri-Axis Sensor |
| Number Of Items | 1 |
| Item Type Name | Pedometer |
Closest rivals on specs
Realalt 3DTriSport 3D Walking Pedometer- Item Weight 0.05 vs 0.09 pounds (-44%)
AVTREK 3D Clip On Pocket Pedometer- Display Size 1.7 vs 1 inches (+70%)
- Item Weight 0.05 vs 0.07 pounds (-29%)
Frequently asked questions
Does the 3DFitBud A420S track distance or calories?
The listed specs describe step counting only; distance and calorie figures aren't part of the feature set.
How is the A420S worn?
It can be clipped to a pocket or waistband, worn on the included lanyard, or carried loose in a pocket or bag.
Does the A420S need charging?
No. It comes with a battery already installed that's rated to last up to 12 months.