No.6 Deep Sleep Mask Serum

Shipping calculated at checkout.

This product is unavailable


Standard shipping within the continental US is free on all orders $80 and over, excluding tax, and after discounts are applied. The shipping takes 5-9 business days after the order is placed using USPS. 

Standard shipping is a flat rate of $18 for all orders up until $79.99.



(Including Processing Time)

Express Shipping Standard


5-9 Business Days

Express Shipping Free


5-9 Business Days



  1. Orders placed before 10:00 AM PDT Monday through Friday (excluding holidays) usually ship within 2-3 business days. 
  2. Order cancellation is only available if the order is unfulfilled. 

INTERNATIONAL SHIPPING is a dedicated website for our US customers. We only ship within the continental United States for orders placed here. 


Orders shipped outside of Korea may be subject to import taxes, customs duties and fees levied by the destination country. Additional charges for customs clearance must be fulfilled by the recipient; numbuzin has no control over these charges, nor can numbuzin predict what they may be.

Customs policies vary widely from country to country; you should contact your local customs office for more information. When customs clearance procedures are required, it can cause delays beyond our original delivery estimates.

Refund Policy

If your order arrives damaged or defective, we can assist with a refund or replacement. We cannot exchange products or accept returns for a simple remorse.

Please be sure to reference your order number with all communications with our customer service team for faster processing.

  1. Only products purchased on may be eligible for a refund or replacement.
  2. We cannot accept items purchased from another retailer for a refund or replacement.
  3. We cannot replace or refund partially used products or products with broken seals.
  4. If a package is confirmed delivered by our logistic partners, but it is stolen or you are unable to locate it, we are unable to refund the order amount.
  5. We cannot accept responsibility for personal damages to an item. If the item has been dropped, stolen, spilled, misused, etc., we cannot accept to replace or issue a refund.
  6. For other inquiries please contact us at

Customer Reviews

Based on 9 reviews
Sasha Wu

I started using this product 3 days ago and have already seen a difference in my skin. I have combination skin, but lately my skin has been more dry. I noticed my skin was moisturized, plump, and hydrated. The skin around my mouth (laugh lines) seem less pronounced as well. Also, when applying makeup over this product, you get the most amazing results! I will definitely be repurchasing!


This is much richer in hydration than I expected. Overall, I liked it, but I suggest this for whose skin is drier than me.

One of the best serums

I just started using it, but it's basically love from the first use ❤ It is nothing short of a miracle in a bottle and I would use this phrase lightly being a of a skincare addict. The serum does what it promises and more. It is very soothing, naturally cooling the skin, super hydrating and gives that so coveted mochi, dolphin skin 🐬. Definitely a winner in my books and will be on the repeat purchase. Love it!

dry skin would love this

i bought it for my mom who had really flaky skin and it seems worked really well last night. Nice!

It’s just MIRACLE

It's my life's favorite, really, why I finally got this great product. I've been wearing a mask lately. Blackheads around my nose are swollen, troubled and dry. My skin is the worst. But my skin has completely changed since I used this product!!!!!!!!!!! The dryness disappeared and the skin began to be soft and shiny like a baby face!! Freaking amazing isn’t it??! I definitely repurchase it !!!😆