Round Four-Prong Flat-Tab Solitaire Lab Grown Diamond Engagement Ring 1.65ctw
All Runivi rings are sized in US sizing. Sizes highlighted are the most commonly ordered (US 6–7½).
| US Size | Diameter (mm) | Circumference (mm) |
|---|---|---|
| 4 | 14.9 | 46.8 |
| 4½ | 15.3 | 48.0 |
| 5 | 15.7 | 49.3 |
| 5½ | 16.1 | 50.6 |
| 6 | 16.5 | 51.9 |
| 6½ | 16.9 | 53.1 |
| 7 | 17.3 | 54.4 |
| 7½ | 17.7 | 55.7 |
| 8 | 18.1 | 57.0 |
| 8½ | 18.5 | 58.3 |
| 9 | 18.9 | 59.5 |
| 9½ | 19.4 | 60.8 |
| 10 | 19.8 | 62.1 |
| 10½ | 20.2 | 63.4 |
| 11 | 20.6 | 64.7 |
| 11½ | 21.0 | 66.0 |
| 12 | 21.4 | 67.2 |
| 13 | 22.2 | 69.8 |
✔ Most commonly ordered: US 6, 6½, 7, 7½
Quick Tips
- Measure at the end of the day, when fingers are largest.
- Snug, not tight — the ring should pass your knuckle with slight resistance.
- Wider bands (4mm+) fit tighter — consider sizing up half a size.
- Between two sizes? Always size up.
- In stock, ready to ship
Our Round Four-Prong Lab Grown Diamond Engagement Ring holds a 1.65ctw round brilliant lab grown diamond in a six-prong setting, its flat-tab prong tips gripping the stone with a clean, precise profile that reads as architectural rather than decorative.
Six prongs distribute holding pressure evenly around the perimeter, offering exceptional security. The plain comfort-fit shank is unadorned, letting the lab grown diamond carry the entire statement.
Available in 10K/14K/18K White, Yellow, or Rose Gold and Platinum.
Ring Details
Item No. - R-DOC-194
Total Carat Weight - 1.65
Approx Gold Weight - 3.46g - 6.72g (Varies by metal type)
Setting Type - 4-Prong Flat-Tab, Open Gallery
Center Diamond Details
Stone Type - Lab Grown Diamond
Carat Weight - 1.65
Shape - Round
Color - E-F
Clarity - VS1-VS2
Your Order Includes
* Free Shipping
* Delivered in Discreet Packaging
* Complimentary Professional Appraisal & IGI Certificate (if applicable)
* Free Lifetime Warranty
Every RUNIVI item is custom-made after your order is placed. We offer free and fully-insured shipping on all orders within US and Canada. Estimated delivery time is 10-12 business days from the date of your purchase.
If you are not 100% satisfied with your purchase, returns are accepted within 30 days of delivery. Learn more about our shipping & return policy.
Why Shop with us
Lifetime Warranty
IGI & Appraisal Certificate
Free Resizing & Shipping
Buy Now, Pay Later
