Review copies, not review buying.

Review Copy Club sells reader matching, delivery, reminders, and reporting. Reviews are honest and voluntary, and authors cannot require positive language or private reader contact.

Rules baked into the product

No guaranteed number of reviews.
No star-rating promises or positive-review requests.
No cash, gift cards, or bonuses to readers for reviewing.
No direct author pressure on readers.
Reader identities and emails are private by default.
Authors must attest that they have the right to distribute each review copy.
KDP Select / KU-sensitive books require author-confirmed permitted delivery.