Here is a list of our most frequently asked questions. Terms & conditions can be found here. If you need additional help, please feel free to contact us.

What does "Kozai" Mean?

  • For those who supported us earlier, you may have known that our company was called "Karoshi Design". Within 3 days after launching, I decided to rename our company to something that better represents what we believe and embody. The word "Kozai" is a combination of two things: 1) "Koz" which is a unit of measurement for gold in a thousand ounces and 2) "ai", which embodies who I am as a person - a Chinese-born Canadian with an appreciation and love for Japanese culture. The word "ai" means "love" in both respective languages. Hence the name, "Kozai", which to me means "love in thousands of gold". The word "Kozai" is also an abbreviation of the word “Kozaiku” where each letter in Kanji refers to the words “Small Fine Craft (小細工)”


> How long will it take to receive my order?

  • This usually takes 2-5 business days but is subject to change with the conditions of COVID-19

> What are the shipping rates?

 Shipment Method (With Tracking)

Estimated Delivery Time

Shipment Cost

Standard Shipping

1-2 weeks due to COVID-19 $7.50

Expedited Shipping

1-2 weeks due to COVID-19 $8.50
2 Day Shipping 2 days - 1 week due to COVID-19 $15.00
FREE Shipping (order over $120) 1-2 weeks due to COVID-19  -


> How do I track my order?

  • After checkout, a tracking number will be sent to the email address provided on your order. Please note that for US shipments it sometimes takes two days to cross the border from Canada, and the tracking code will not start updating until the package has reached the USA.
  • Feel free to track your package here!



> What are the materials made of?

  • Stainless Steel 316

Are any of your products made of Sterling Silver?

  • This is in our agenda! We hope to switch over to Sterling Silver in the near future so stay tuned!

> Do you have a retail store location

  • As of now, we believe e-commerce is the way to go! This is not in our agenda but with your support, it may be possible.

> How do I best care for my accessories

  • Our rings will not rust but to maintain quality, we suggest taking them off before washing hands, showering or working out. This applies more so for the Reminisce ring as this has a spring within the locket.
  • Do avoid grinding on hard surfaces as this will scratch the steel, unless you are going for a rustic look.
  • Clean with microfiber cloth or 100% cotton fabric gently. Got none? Use your clothes!
  • Please avoid corrosive liquids such as seawater & brine. This also includes liquids like commercial jewellery cleaners as they tend to be too harsh for electroplated products. Feel free to use something soft like dish soap instead.
  • Store in a safe, dry place when not worn.



> How can I find out my size?

  • It is always best to consult with a jeweler to ensure accuracy but if this option is not made available for you, please feel free to print out and use the diagram below for an accurate measurement:
Size Measurements
Once done, refer to this chart below to determine your US ring size:
Karoshi Ring size

> I don't see my size, will you be making my ring size?

  • As of right now, we only offer rings in select sizes due to our capacity. However, in the near future and due to popular demand, we will bring a wider variety of sizes to our clients. You may have to wait a bit longer if you have the hand size of Kawhi Leonard.