From fasttech web site
What items are restricted or potentially restricted by the customs and/or air mail shipping services?
For customers' convenience, FastTech carries a wide variety of products, offers a number of shipping methods, and ships to over 200 countries around the globe.
While the vast majority of customers happily receives their products in a timely and orderly manner, at times packages containing certain types of products may be returned to FastTech by the chosen shipper or the destination country's customs. When a package is rejected or returned, FastTech takes steps to resend or refund customers.
List of products that are returned/rejected more often than others:
1.Lithium battery cells (e.g. 18650, 18500, 18350, CR123A, 14500, 10440 lithium batteries, both primary and rechargeable).
2.Flammable liquids such as e-liquids, perfume, and essential oils.
Note that since these products are classified as "dangerous goods" by the Post Union, they are sometimes rejected by air mail service providers such as Hong Kong Post. Post FastTech do pay attention and pack these products with special care, however, product packaging cannot and does not alter how these products are classified by the Post Union.
In addition, despite the Post Union classification, each postal carrier has their own rules and practices. For example, Singapore Post is officially okay with e-liquids. For this reason, FastTech implements automatic packaging routing that redirects packages to various carriers according to your shipping country and content of orders. This automatic routing is applied when you select the "Registered Air Mail" shipping option during checkout.
Last but not least, while most packages do get through all the hops and properly delivers to customers, of you are looking for 100% guaranteed delivery time for lithium batteries and liquid products (i.e. you cannot accept delays caused by rejects and/or inspections), FastTech is able to ship through DHL via their Dangerous Goods shipping service. A custom shipping quote is required as shipping costs depend on the destination country, and quantity/type/brand of items ordered (which affects DHL packaging requirements).
now my 2 cents - they will be shipping yours buy USPS (yes, the United States Post Office) - I just ordered more batteries and shipping was no longer than normal - about 15 days to South Dakota (and most of that is in the US - my orders from fasttech see more of the states than I have)
