In wake of Amazon raising prices on its Prime service, there is a new membership about to be sold. Ironically after putting brick-and-mortar book stores in a tight spot several years ago, Amazon is launching Prime Book Box to deliver hardcover children's books.

Of course, only Prime members are going to be eligible for the new offering. Each box of books is going to cost $22.99. According to Amazon, this equates to a 35 percent discount over buying all of the included books separately.

Customers can choose to have books delivered in one, two or three-month increments. As kids grow up, Amazon recognizes that different books are needed. There are four age groups that can be selected at any time ranging from newborn on up to 12 years old. For the youngest that cannot actually read, four board books can be substituted in place of two hardcover books.

In terms of book selection, Amazon will be asking customers about the reader to tailor picks. The books part of the subscription service "include classics that have stood the test of time as well as hidden gems that our editors couldn’t put down—stories that your reader can enjoy again and again."

If consumers are unhappy with the recommended books, it will be possible to swap books before an order ships. Amazon will also review purchase history to ensure that any previously purchased books will not be recommended or included in boxes. Should customers be unsatisfied with any books, standard return policies apply.

One caveat of the service is that Book Box orders cannot be combined with other orders. As a result, add-on items that require orders totaling over $25 will not be able to be combined with these specialty shipments.

US-based Prime members are now able to request an invitation to join the new service. Amazon will be e-mailing customers once the service is fully available.