Legal notice

Seller Company:

Boost Kernel Co., Ltd.

Company Director:

Takahiro Ishisaki

Address:

4F, VORT Building, 1‑14‑8 Shimbashi, Minato‑ku, Tokyo 105‑0004, Japan

Phone:

+81-(0)3-6822-5146

Email:

info@jstarcards.co.jp

Website URL:

http://www.jstarcards.jp

Support Hours


Business Hours: 11:00‑18:00 (Excluding Saturdays, Sundays and Japanese national holidays)
※Please use the inquiry contact form for messages outside business hours.

Product Prices


Please refer to each product page for pricing details.

Shipping Fee


  • Shipping Fee： Free shipping within Japan.
    ※Domestic Japanese orders will generally be delivered to your mailbox via ○○. Delivery date and time cannot be specified, please kindly note.

Additional Charges (Excluding product price)


No extra processing fees for convenience store payment or cash-on-delivery.

Delivery Lead Time


Orders will be shipped within 5 business days from the order date.

Shipments are sent via Japan Post Yu-Packet; delivery takes 2 to 5 business days after dispatch depending on the destination.

Payment Options & Billing Timing


Accepted payment methods: Credit Card, Wallet Pay (Apple Pay, Google Pay), Shop Pay

  • Credit Card: Payment is authorized and charged at the time of order placement.

Return Period

Returns are only accepted for unopened products within 7 days from the purchase date. If you wish to return goods, please contact us in advance via the inquiry form.

Refund & Return‑Shipping Policy

Full refunds are offered only for unopened, unused items when we are notified within 7 days after delivery. Return‑shipping fees for customer‑requested returns shall be borne by the customer.
However, if products suffer from initial manufacturing defects, our company will cover return‑shipping costs and provide either a full refund or product replacement.
Refunds will NOT apply under the following circumstances:

‑ Outer protective film is damaged or opened

‑ Product tags or security seals have been peeled off

‑ Traces of use, stains or foreign odors are found

‑ Product substitution is suspected
After receiving and inspecting your returned item, refunds will be processed according to your original payment method, including credit card, bank transfer and mobile payment.