- TrueGrade tested — passes our 25-point inspection
- Fast, tracked shipping
- 90-day returns
- Up to 70% cheaper than new
Apple Watch Series 4 40mm – Silver Aluminum/Black Sport Band
Buy a certified refurbished Apple Watch Series 4 40mm in Silver Aluminum/Black Sport Band from $86 at Device Giant — every Watch Series 4 40mm is fully tested under our 25-point TrueGrade inspection, ships unlocked-ready, and is backed by our 90-day warranty and free US shipping. The Apple Watch Series 4 40mm, released in 2018, marked a significant leap forward for Apple's wearable technology. It introduced a stunning edge-to-edge display that was 30% larger than its predecessors, all while maintaining a similar overall footprint. This model was the first Apple Watch to feature an Electrocardiogram (ECG) app, allowing users to take an on-demand ECG directly from their wrist, a groundbreaking health feature at the time. Compare grades, storage and carrier options below and save versus buying new.
Watch Series 4 40mm key features
- Larger Edge-to-Edge Display
- ECG App (Electrical Heart Sensor)
- Fall Detection
- Faster S4 Dual-Core Processor
- Swimproof (Water resistant 50m)
- GPS, GLONASS, Galileo, QZSS
- Optional Cellular Connectivity
- Emergency SOS
Watch Series 4 40mm full specifications
| Display | 1.57 inches LTPO OLED Retina display, 394 x 324 pixels, 60Hz |
|---|---|
| Processor | Apple S4 with 64-bit dual-core processor |
| RAM | 1GB |
| Storage | 16GB |
| Rear camera | N/A |
| Battery | 225 mAh, Magnetic charging cable |
| Build | Aluminum case or Stainless Steel case, Ceramic and sapphire crystal back, Water resistant 50 m |
| Operating system | Apple Watch OS |
| Network | 4G LTE and UMTS (Cellular models only) |
| Biometrics | Wrist detection, Passcode |
| Dimensions | 40 x 34 x 10.7 mm |
| Weight | 30.1 g |
Why buy a refurbished Watch Series 4 40mm?
- Save big — a used Watch Series 4 40mm starts at just $86, well below retail.
- 25-point TrueGrade tested — battery, screen, cameras, buttons and network all verified.
- 90-day warranty & free shipping on every Watch Series 4 40mm.
- Better for the planet — buying refurbished keeps e-waste out of landfills.
- Upgrade to a newer Apple Watch model with more advanced features.
- Get cash for your device, which still holds value due to its health and safety features.
- The Series 4 offers a premium smartwatch experience for those looking for an upgrade.
Watch Series 4 40mm pros and cons
Pros
- Groundbreaking ECG and Fall Detection features
- Significantly larger display than previous models
- Fast and responsive performance with S4 chip
- Excellent fitness and activity tracking
- Optional cellular connectivity for independence from iPhone
Things to know
- Battery life is typical for a smartwatch (up to 18 hours)
- No always-on display (introduced in Series 5)
- Older model, lacks some newer features like Blood Oxygen sensor
- Requires an iPhone for full functionality
Carrier compatibility
This refurbished Watch Series 4 40mm is available unlocked and compatible with GPS+CELL. Check the carrier selector above — we only show options we have in stock so you can buy the exact Watch Series 4 40mm that works on your network.
Storage options
Choose the Watch Series 4 40mm in 16GB. Pick more storage for photos, apps and offline media.
TrueGrade condition guide
- Grade A — Excellent: like-new, minimal to no visible wear.
- Grade B — Great: light signs of use, fully functional.
- Grade C — Fair: visible wear at the best price.
- As-is / damaged: clearly described cosmetic or functional notes, priced accordingly.
Watch Series 4 40mm — frequently asked questions
Is the Apple Watch Series 4 40mm still worth buying in 2026?
Yes — with Larger Edge-to-Edge Display and a proven design, the Watch Series 4 40mm remains a great-value refurbished phone, especially at $86 with a 90-day warranty.
Does the refurbished Watch Series 4 40mm come unlocked?
Most Watch Series 4 40mm units are sold unlocked and ready for GPS+CELL. Carrier-specific versions are clearly labeled in the carrier selector.
How much does a used Watch Series 4 40mm cost?
At Device Giant a refurbished Watch Series 4 40mm starts from $86, with the exact price depending on storage, carrier and TrueGrade condition.
What's included with a refurbished Watch Series 4 40mm?
Your Watch Series 4 40mm ships fully reset and tested with a compatible charging cable, a 90-day warranty and free shipping. Accessories vary by condition.
What do the condition grades mean?
See the TrueGrade guide above — A (excellent), B (great), C (fair) and clearly-described as-is options, so you can pick the right balance of price and cosmetics for your Watch Series 4 40mm.
Every device is graded for cosmetic condition and tested for full function against our TrueGrade 25-point inspection. Buying refurbished keeps a working phone out of landfill — better for your wallet and the planet.
Better for your wallet & the planet
Every refurbished phone is a win for the planet
Choosing refurbished over new keeps a working device out of landfill — and skips the carbon, water and raw materials it takes to build a brand-new one. A small choice with real impact.
Less carbon
Most of a phone's lifetime emissions come from manufacturing. Reuse skips nearly all of it.
Less e-waste
Millions of devices are trashed every year. Every reused phone is one less in a landfill.
Fewer raw materials
No new mining of rare metals, no manufacturing water use — the device already exists.
Circular by design
When a device truly can't be saved, we harvest its working parts and recycle the rest responsibly.
Refurbished is not a compromise. It is the smarter, greener way to buy tech, and every TrueGrade device ships tested, graded and ready for its second life. See how we do it →
