This product is either discontinued or we cannot get that from suppliers.
QNAP Extended For TS-673 Series EXT1-TS-673, QNAP Service & Support, QNAP Network Services / Support.
This is a simple and powerful statement that QNAP products are built to last. If the standard warranty is not long enough, QNAP Extended Warranty Service coverage offers our customers worry free protection well into the future.