Yes. If the price drops within 30 days of your purchase, we refund the difference. This applies to all platforms (official site, app, and authorized third‑party stores).

Only one discount can be applied per transaction.

Orders placed during the promotion are processed within 1–2 business days. Shipping times vary by location but typically take 3–7 business days

Note for pickup and truckload (LTL / freight) orders: Delivery timelines may vary depending on actual order circumstances (e.g., pickup location, load consolidation, carrier schedule).

Yes, free shipping is included for all products, except: LTL (Less Than Truckload / freight) products Self pick-up only orders

For LTL and self pick-up orders, shipping costs or arrangements may apply separately.

Yes. All our lithium batteries include a 5-year warranty and free technical support.

Yes. Sale items are covered by our 30-day return policy, as long as the battery is unused and in original packaging.

You can still reach our customer support team via email or phone. Sale or not, every customer receives the same post-sales service.

While sales strategies and platform fees may vary, if you find a significant price difference, please send a screenshot showing the lower price to our after-sales team at service@humsienk.com for review. Once verified, we will refund the difference.

Please note: Price difference claims must be submitted within 7 business days after your order is placed. The 30-day price protection policy applies only to Member Day and Black Friday / Cyber Monday promotions.