Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND

Fy Ring SE DIAMOND

A smart ring set with natural diamonds

Diamond Silver  –   ¥39,600

Size i

Sizing runs differently from standard rings.

Not sure of your size? See the size chart, or order the sizing kit below first.

Free shipping · Free gift wrapping

Why a ring

Not a camera watching them.
Not a call they have to answer.

There have really only been two ways to know how a parent living far away is doing. Neither one holds up over time.

The old way

Home cameras

You can see. That's the problem.

The room shows up exactly as it is — getting dressed, visitors, all of it. The person being watched stays on guard, and the person watching feels intrusive. Privacy goes, and it gets uncomfortable on both sides.

The old way

Calls and messages

No pressure. And no answer either.

What comes back is “I'm fine.” The message is read, but you still don't know whether they slept. The more they try not to worry you, the less you actually learn.

This product

A smart ring

Nothing is filmed. Only how they're doing.

They just wear the ring. Sleep and heart rate reach the app on their own. You never look into their day — you only notice when something changes. Instead of “how have you been,” you can ask “did you sleep alright last night?”

Fy Ring SE DIAMOND in three finishes

The Design

Wear it the way you'd wear
any other ring.

A ceramic exterior with natural diamonds set along angled lines. It catches the light as your hand moves. With the plain black finish alongside the two diamond-set ones, there is a version that goes with what you already wear.

While it's on, sleep and heart rate are recorded automatically. Nothing to press, nothing to open. It starts as simply as adding one more piece of jewelry.

Three finishes.

Two set with natural diamonds, and one plain black. All three are identical inside.

Black Plain, Diamond Gold and Diamond Silver
Black Plain
Diamond Gold
Diamond Silver

Seven readings,
recorded on their own.

Sensors on the inside of the band record throughout the day. There is nothing to operate.

  • SleepDuration, quality, score
  • Heart rate & HRV24-hour rhythm
  • StressDaytime trends
  • Skin temperatureChange from your baseline
  • Blood oxygenSpO₂ trends
  • Steps & caloriesDaily activity
  • Activity scoreAn overall daily read
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND
Fy Ring SE DIAMOND

Fy Ring SE DIAMOND is not a medical device. It is not intended to diagnose, treat, cure, or prevent any disease. Readings are for general wellness only.

Magnetic charging case

Charging

Set it down. That's the whole step.

A magnetic charging case in clear housing — no orientation to line up. One charge lasts up to 7–10 days, and a full charge takes about 90 minutes.

Battery life varies with ring size and use.

No subscription

$0 per month, forever.

There is no membership fee after you buy. Your data stays available in the app, and the AI assistant flags changes and answers questions when something feels off.

Specifications

The ring
Width
8 mm (0.31 in)
Thickness
2.6 mm (0.10 in)
Inner diameter
17.4–22.1 mm (0.69–0.87 in)
Weight
3.6–4.5 g (0.13–0.16 oz), depending on size
Outer material
Ceramic
Inner material
Hypoallergenic material
Finishes
Black Plain / Diamond Silver / Diamond Gold
Diamonds
Natural diamonds
Setting
Diamond Silver and Diamond Gold are set with natural diamonds along angled lines. Black Plain has no stones.
Size chart
SizeInner diameterInner circumference
US 717.4 mm0.69 in54.7 mm2.15 in
US 818.2 mm0.72 in57.2 mm2.25 in
US 919.0 mm0.75 in59.7 mm2.35 in
US 1019.8 mm0.78 in62.2 mm2.45 in
US 1120.6 mm0.81 in64.7 mm2.55 in
US 1221.3 mm0.84 in66.9 mm2.63 in
US 1322.1 mm0.87 in69.4 mm2.73 in
Order the sizing kit before buying to confirm your size.
Tracking and app
Readings
Sleep / heart rate and HRV / stress / skin temperature / blood oxygen / steps and calories / activity score
App
Syncs automatically. No subscription.
Compatibility
—
Battery and water resistance
Battery life
Up to 7–10 days per charge, depending on size and use
Charge time
About 90 minutes
Charging
Magnetic charging case
Water and dust
IP68
In the box
  • Fy Ring SE DIAMOND
  • Magnetic charging case
  • USB-C cable
  • Ring box, gift wrapping available

Questions

Are the diamonds natural?
Yes. Diamond Silver and Diamond Gold are set with natural diamonds along angled lines on the band. Black Plain is a plain finish with no stones.
What if I don't know my ring size?
Order the sizing kit ($18) first and try it on. When you buy the ring, the $18 is refunded in full.
If you skip the kit and the ring doesn't fit, return shipping for an exchange is at your expense.
Can I shower or wash dishes with it on?
Yes. The ring is rated IP68, so everyday contact with water — handwashing, showering, dishes — is fine. You can leave it on.
Is there a monthly fee?
No. The app is free to use after purchase.
Is this a medical device?
No. Fy Ring SE DIAMOND is not a medical device and is not intended to diagnose, treat, cure, or prevent any disease. Readings are for general wellness and informational purposes only. Talk to a healthcare provider about any health concern.

Something you'd want
to wear every day.

You don't need to know your size to start.

Fy Ring SE DIAMOND
¥39,600