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K KORKUAN

Smart Ring Sizing Kit, Compatible with Oura Ring4, Measure Finger Size Before Buying Ring, Size 4/5/6/7/8/9/10/11/12/13/14/15 (White)

  • Based on 11 reviews
Condition: New
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$8.99 Why this price?

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This item is eligible for return within 30 days of receipt

To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.

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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, Jul 14
Order within 16 hours and 24 minutes
Available payment plans shown during checkout

Features

  • Compatibility: Compatible with Oura ring sizing kit can facilitate users to determine the appropriate ring size (Note: Using lubricating oil makes it easier to wear)
  • Easy to Use: The user simply follows the instructions on the measuring card, places it on the finger, or directly measures the circumference of the finger to find the corresponding ring size
  • How to measure and check size: Place the sizing tool at the bottom of your finger to make sure it doesn't spin freely. We recommend wearing for more than 24 hours to determine the most accurate size, for the best data and comfort
  • Finger selection: Suitable for all fingers, both left and right. Choose the ring size based on the exact size of the finger you intend to wear the ring on
  • High Accuracy: The measuring card has been precisely designed to ensure that users can measure accurately to avoid wearing discomfort caused by inappropriate sizes

Operating System: Android Wear 1.0


Memory Storage Capacity: 1 GB


Special Feature: compatible with Oura Ring Gen4


Battery Capacity: 600 Amp Hours


Connectivity Technology: USB


Battery Cell Composition: Lithium Polymer


GPS: No GPS


Shape: Rectangular


Screen Size: 4.72 Inches


Brand: K KORKUAN


Package Dimensions: 6.81 x 4.49 x 0.47 inches


Item Weight: 1.44 ounces


Batteries: 1 Nonstandard Battery batteries required.


Date First Available: March 28, 2025


Manufacturer: K KORKUAN


Country of Origin: China


Standing screen display size: 4.72 Inches


Memory Storage Capacity: 1 GB


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Jul 14

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • useful smart ring sizing set
I'm interested in the Oura Ring 4 but it's incredibly important to get the right size. I already checked the size at the store display but I plan on getting one after I lose a bit of weight and want to check how the ring size changes over time. This is much more convenient to have a whole set at home than driving back to the store. The set has everything from 4 to 15 and they're all clearly labeled on the storage sheet. This also allows me to wear the sizer for awhile to get a feel of how comfortable/uncomfortable it is to have while working and doing daily chores. Be careful to check if the storage sheet is facing up before pulling out of the box. I ended up spilling them all and having to match each sizer to its spot. ... show more
Reviewed in the United States on June 23, 2025 by JJH42
    • Absolutely Use This Before Buying an Oura Ring
Absolutely use this before buying an Oura ring. I was thinking of buying an Oura ring and wearing it as a wedding band. I generally wear a size 7-8 ring. However, when I sized my ring finger with this guide, it turns out that for Oura I'm a size 9. Plus, it gave me a sense of how thick the ring actually is, because it's not thin. It's a big purchase to make online without sizing your finger first. ... show more
Reviewed in the United States on June 22, 2025 by Laura
    • Works as needed, quick and easy
Need a quick and simple ring measuring kit, and this fits the bill. It took seconds to find multiple ring sizes, and we now have this set stored, ready for the next time we need to know ring sizes. No issues with use and accuracy.
Reviewed in the United States on June 24, 2025 by Lowell Chapman
    • Great little tool
Perfect to have around if you're always forgetting your ring sizes, or have a need to quickly size others frequently. Very simple design - just a sheet of molded plastic with labeled pegs, and a set of white plastic rings you can quickly take off and slide on a finger to see how they fit.
Reviewed in the United States on June 18, 2025 by A. Rand
    • Pretty accurate and helpful
I already have an Oura Ring 4 and am trying to help someone else figure out what size to get for themselves. When I got mine, I went to best buy to try one on in person, but this kit is actually quite accurate and helpful so I would say it is worth it. The size that I currently have is an exact match to the one in the kit so it is pretty reliable. ... show more
Reviewed in the United States on June 11, 2025 by Suitsme
    • Universal Smart Ring Sizing Guide
Review Image by Richieee Richieee
Universal Smart Ring Sizing Guide Good universal smart ring sizing guide for ordering. (+) Physical rings really help determine the most accurate & comfortable size to order.
Reviewed in the United States on May 28, 2025 by Richieee Richieee
    • oura ring 4
Perfect fit, various sizes, clear instructions and simple size measurement methods enable you to easily determine the correct ring size.
Reviewed in the United States on May 27, 2025 by Natividad
    • The quality is very good
The quality is very good. It enables you to choose the correct size.
Reviewed in the United States on May 27, 2025 by Tracy Nancy

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